It’s not illegal for a celebrity to launch a meme coin or collectible. It’s not as clear if the President and his direct family can do the same.

Anti-bribery/corruption is the concern with the coins (just as it was with his hotels in the first administration). Not the legality of the coin.

But it’s moot, this admin has decided that norms don’t constrain it and it will not allow investigations into itself. So it’s de facto legal.