@OP Previous posts are very clear & valid.
I would add another point for you to consider. If you want / like BA travel before you go too far try a few of your intended destination on dummy bookings to see how many avios you will pay & HOW MANY DOLLARS IN FEES ! This will allow you to consider whether you are ready to to try and stick to BA. Mind you avios can be spent on other One World airlines too but you will still pay higher miles / $$$.

As to the bloggers, yes practically all are in it for business, very repetitive. Some make six figures. TPG has build a good company, according to him he used to work on Wall Street, quit and is a full time blogger.