Most college players think they're NBA material, regardless of how unrealistic that may be. A large percentage of these guys going into the portal think they're improving their chances. Ergo, decent players on terrible teams transfer. A lot. It should be expected.
Yes, now there's an element of money. Fundamentally, though, it's still about the player improving their situation, whether that's about financial or basketball reasons.
I understand this is no longer what a lot of us grew up with and you might not like it. I do think some rules are needed, but we'll all adapt. Even internet faux-tough guys.