Some of the problem lies in the fact that many necessary jobs just aren't fun, or at least are physically demanding regardless of the fun level. That doesn't mean they can't still be satisfying on some level, of course.
Another part is the question of whether there is sufficient demand for the goods and services from more fun jobs. We can't escape the supply/demand curve. Thanks to the internet, we can find new opportunities sometimes though.
There are various obstacles, some cultural, some legal, to fun kinds of entrepreneurial activity. Just look at the mess of the US trying to "regulate" (I say strangle) crypto.
Finally, the entire market is distorted by fiscal policy. Inflation, federal reserve balances, incentives of regulatory policy... These factors and more complicate long-term planning.