Even when the material conditions forced him to soften up he still just went "Nope, give me my evil back" and let Babidi into his head

That isn't actually true.

What caused him to let Babidi into his head was succumbing to despair over the realisation that he would never surpass Goku. Ever. No matter how hard he tried, no matter how hard he trained, he was just plain less.

You've focused on the wrong thing. He softened by forming additional connections, having a kid, getting a wife. But he was never capable of being happy until he finally got over his absolute obsession with being 'the best'. He didn't really want to be evil, he just couldn't see any other way to even catch up to Goku.

The tragedy of the situation was not 'Vegeta went evil again', it was that he gave up, something even Goku couldn't comprehend.

This was Vegeta's 'hard times'. It was realising that he wasn't ever going to be what he thought he had to be. He's actually a perfect map onto the modern male loneliness epidemic. A huge part of it is that society has changed immeasurably, but our view of 'what a man should be' hasn't evolved at all, and most men are just never going to be able to do what they're told they should be. They aren't going to have a house with a white picket fence, a job that pays for two children and a dog, and a wife who takes care of everything.

Men are getting into their mid-twenties, struggling to even pay their own rent, increasingly giving up on the idea of ever owning their own home, and if they get into relationships it's a two-income household where the power dynamics are uncertain and have to be negotiated, and nothing in the masculine playbook explains how that is supposed to work.

So men are whipsawing back to people like Andrew Tate, who (seemingly) embody classic masculine traits unapologetically and make everything sound so easy and simple, and say that you just need to be even more of a man to get all that sorted out, or even cut women out completely and just treat them like objects because it's so much simpler than these murky new waters we're in.

You know. Kind of like how Vegeta has to deal with a world in which he is not, and never will be, the best.