You can downgrade version on fdroid, thats what I did

It is stupid to buy something just to avoid taxes. If it helps you grow a business - sure. But not to avoid paying taxes. As I said it depends on your goal. If you want your business to grow, have the best seed round or in general company valuation - yeah, reinvest. But if it is business that you do to make a living, it is stupid to spend everything just to not pay taxes

Tbh it depends. Usually it is like you say, but it depends on the goals of the owner. Steam is private for years and they make profits. Also if you have smaller business and you treat it like your business, you just want to get sallary for what you do. “Dumb” is too strong word as it depends on your position and goals