Remember, you're on a forum inhabited by frequent travelers. The opinions of FlyerTalkers might not be representative of the general working public.

IMHO, not before mid-2022. Companies are making major investments in upgraded videoconferencing capabilities during the pandemic, the 2021 corporate budgets (which assume minimal travel) are being finalized as we speak, and the legal and insurance risks won't become acceptable for business travel until a vaccine (and some therapeutics) are in widespread global distribution.

And even once business travel resumes, expect "permanent" 40-60% reductions in travel spend compared to pre-pandemic levels. Travel costs are a substantial overhead expense, and use justifications will become much more stringent (e.g., OK to travel for big deal signings and the biggest customer pitch meetings, everything else is a videoconference). Corporate conferences will be among the last events to return given the inherent risk and substantial overhead costs of bringing a bunch of people into one space.

I think eventually travel will come back. Decreasing face-to-face meetings as compared to other corporations may lead to competitive disadvantages. The old penny-wise and pound-foolish situation.

A convention needs to be planed and organized well ahead of time.
No one in his right mind will invest/pay/make commitments for a future convention in 2020.
So, i highly doubt that there will be any significant conventions in March/April 2021.

Again, it's not enough that a vaccine is approved. It needs to be produced, distributed and needs to show that it is safe and effective. If we still have local Covid-19 outbreaks (despite a vaccination push) in Q2 2021, then the travel restrictions won't be lifted.
Any serious key politician will wait until the end of Q2 2021 to make a decision whether to reset entry/exit immigration policies to pre-Covid-19 levels.

One must not forget that the Trump + EU travel bans have virtually destroyed the transatlantic travel market. Only once these travel bans had been rescinded from both sides, business travel + conventions + onsite workshops will pick up again.
Don't expect that Biden (if he wins) will lift the travel ban on January 20, 2021! In January 2021 we won't be there yet.
If Trump wins, I expect that his top immigration lobbyist (Lou Dobbs) will have persuaded him to only lift the travel ban only once the US Visa Waiver Program had been abolished. Note: Trump listens to Dobbs and Dobbs hates the Visa Waiver Program ever since 9/11.

Companies are getting a taste of reduced travel costs and they're all liking it. Unless you have a physical task to do onsite I expect much of it will not return. The days of travelling for meetings are likely over.

I have a convention scheduled in April, I hope this marks my return to conferences

A vaccine being approved and distributed is a good step, but it will be one of the last steps - what needs to happen is that Covid spread numbers need to decline. Other developments (increased testing, better mask wearing, more people developing antibodies) may slow the spread significantly going into Jan/February.

I don’t think they are completely over but I think they are likely drastically reduced. We have been operating under a paradigm, or a couple of them, that have been in place from like 1960 or so. In that people jumped on jets to travel for various business purposes. Some of that is still needed. But the technology has been building that could replace much of it. The pandemic has solidified those changes. I don’t see us going back to what it was before.

The era of corporate tourism is mostly over.

It has already started for me, but a fraction of what it would have been pre-Plague. Having onboarded new customers and completed assignments entirely remotely I’m not sure the travel will come back fully for some time. However there are some things that simply work better in person...you try doing a site walkthrough on FaceTime?!

The thing I wonder about, what happens when your competitors send someone to a customer in person? They may get the business instead of you. There are many situations where there is no substitute for being there. My work requires me to be there and to physically touch things. I look forward to being able to do that too. I am not quite so pessimistic about the future of business travel as some.

Sure, there will absolutely be worthwhile justifications for business travel once it's safe to travel (and, to congregate in some numbers in the office setting). But unlike pre-pandemic, when air travel was often the institutional default and videoconferencing the exceptional case, post-pandemic the reverse will hold true as modus operandi for many organizations. To varying degrees, the world's airlines are preparing for this new reality.

I think you really expressed it well. For most things the default has changed.

What if the customer Is working from home? Not all will be doing that of course but far more than were doing it before. I think things have fundamentally changed.

I think there will be some conferences in 2021, mostly because many organizations typically book convention/conference sites out years in advance. Hotels are hurting, and many have stopped being willing to negotiate for rebooking, and the cancellation penalties are anywhere from six to eight figures depending on how many hotels are involved. Combine that with the fact that meeting insurance policies have changed so a communicable disease clause isn’t available, so company can’t cancel their meeting and their claim their insurance. Based on those factors I think some organizations will try to hold conferences and conventions in 2021. Personally, I just think that it’s going to be financially unworkable, especially if social distancing is still needed.

The big question is how valuable human contact is for business and how much revenue it can bring. I would bet on it having some benefit, it's a human nature to be social.

If businesses can earn extra money by offering personal contact, they will return to travelling. My thinking is that if personal contact weren't profitable, someone would exploit it years ago, do everything via teleconferences and gain a significant cost advantage against its competitors - effectively killing business travel long time ago.

It's easy not to travel if your competitors don't travel either. It may not be that easy when they do. Based on my personal experience from a region where restrictions aren't very severe and we don't have the social distancing policies, there is a strong will to do in-person meetings wherever possible. Long business trips are not back yet, but if we're meeting with someone who's less than ~4 hours drive, doing it in person is the standard again. I think people who predict videoconferences to be the new standard are seriously underestimating human nature.