Pre-March 2020 visas are cancelled, new visas are almost impossible to get, all the consulates are closed to visitors and you can only process things via mail, the travel health code is indeed used by the Chinese missions abroad to make coming to China difficult, not just for foreigners but also for their own citizens. There are many stories of being unable to get the green code despite having everything lined up visa wise and stories of Chinese citizens being denied the code for spurious reasons.

Your advice about getting the visa and WP would have been useful in 2019 but it is just bad advice at the moment IMHO. I don't believe any dodgy agent is going to be giving out PU letters at the moment and there is no way you can bribe the guards at the quarantine facility to make your life easier in quarantine(I've been through this). Getting the Chinese vaccine doesn't mean they'll give you a visa either. Unless the poster has a current Residence Permit or works for Apple/Tencent/Goldman etc with a verified need to come to China then it's gonna be extremely hard to get a visa. Having a Residence Permit and leaving China doesn't necessarily guarantee they'll let you back in either (hence the travel code).

China has taken a "zero cases" policy when it comes to Covid, which is why they have recently increased the length of the quarantine in just about every province to 21 or 28 days. They use the travel health code, the ridiculously strict policies limiting flights into China and the quarantine measures to do everything they can to discourage people from coming here. Since they continue to maintain the "zero cases" as a goal, I don't see how any semi-normal business travel will be allowed for this year or next year. Tourism will likely not be allowed for at least a few more years. I just can't see them opening up in any meaningful way this year after all the measures they have taken to control the virus and all the warnings they have given their people about the deadly nature of Covid.

Whatever visa you get, coming to China means at the very least spending a half month in quarantine after arrival and that fact alone will turn off all but the most dedicated visitors.