As far as I know, (based also on what I've observed in the past couple of months) Bitcoin and cryptocurrencies in general are already hit the mainstream level, making it be adapted by many companies, used by many applications, and even made crypto a normal and accepted mode of payments among various businesses. But in fact, some countries were still on the process of adapting and progressing with the system of crypto, whilst some are taking it in legal actions and sees it as illegal. Hence, it was mainstream in many or rather most countries, but not totally in all.