Florence Nightingale had a permanent subsidy from her very wealthy father. (Essentially IBI). She chose to do something with her life. But there were thousands of times the number of people with wealthy parents than there are famous people. That is because most people really won't do anything special with themselves, unless they have to.

Granted, society benefits most from the work of the exceptional, so it may still be worth it.

I also don't believe that we have eroded free time over the last generation. As one example, many now have a robot vacuum cleaner, which frees whatever time they previously spent vacuuming. They may be spending a lot of their time on things, but as long as those are things by choice, it's still free time.