There are many different social media platforms that can be used to promote Bitcoin. Facebook, Twitter, Reddit, TikTok, and others related to it are still there. In fact, all social media platforms can be used by exploitative people or scammers.
Most of the advertisements I see about bitcoin on social media, I believe, are doing so for their own personal interest. Most of them are scammers looking for someone to scam, some of them claim to be signal providers, and some are looking for referrals. When you believe every advertisement you see about bitcoin on social media and decide to follow what they say, you are likely to be scammed at the end because they are doing the advertisement for a purpose.
Maybe when the price of Bitcoin rallies in the market, Instagram will withdraw its ban on Bitcoin.
I can't really remember when last I used Instagram, and I don't know anything about the ban that the OP is talking about. This is my first time hearing about the ban, I don't know how true it is, but I know the ban will just be temporary, just give it a few months, and I am sure the ban will be lifted. Actually, I don't really know why they decided to ban bitcoin, because it's not only Instagram that's used to advertise bitcoin. Even though we know that most people doing the advert are doing it for a purpose, other social media's are also used for bitcoin advertisements, but they didn't ban bitcoin.