I think there is something else at work here, too, which you kind of implied perhaps.

I will say things like: I wish I could paint all day long.

But during those few periods of my life when this was possible, I became very tired of painting, and wished I could do something else. So, it is a moving target.

These days, I'll say: I wish I had never ever painted. I just want to work on old/custom cars all day. But to do that lucratively, you have to deal with other people. And (as someone has famously said), hell is other people. I would quickly lose my patience trying to satisfy the demands of quirky custom car customers.

I don't reckon you can win at this game, no matter how you slice it.