If Jeff Bezos said "I've got enough", perhaps Prime Video wouldn't exist, which would be a net loss to their employees and their consumers who pay for that. It would also mean that Netflix and Disney would very likely be charging more, due to less competition.

Now, if you meant he should just be running this kind of stuff pro bono, consider that Prime Video cost about $16 billion USD per year just for content last year. Even if he puts all his wealth into it, Prime Video would last less than 10 years as a free service before it had to shut down.

I think we should tax the hell out of billionaires by the way, but that's an unrelated issue.