In my nation (and I am guessing for OP as well) there is a good chance that you could have a law that says as long as there is an agreement, anything could be used. Like for example you could give 100 cows and get a land, and yes that is barter we used thousands of years ago, but it still works even today.
This is why I believe that we should not be focusing on the part where if it is legal or not, but the part how he used his bitcoin income on something that is tangible. Is it a better idea? I do not know, if he can turn a profit then it is a great idea, but if you ask me I would have stayed in crypto because I do not know much about any other business to be fair.
This is true that people will need to figure out how to use bitcoin without getting in front of the laws, I mean it's possible and it's there, we just need to get two parties to agree to it. I have seen plenty of people selling stuff in my nation, via telegram of course.
There are "second hand market" type of telegram groups for crypto, they sell their playstations, they sell their toys and gadgets and what not, they sell even cars, few try home because that's a bit hardcore, but people try to do a lot with it. I have seen even people do installments, like a debt, but that's scary because if you have to pay a certain amount of coins, and the price of that coin goes up, you are overpaying for it, but it exists.