If you are an investor you are going to have a hard time investing into companies because there aren't going to be a lot of physical companies being founded and you'll see a decrease in internet companies being founded. Also, starting a business would be seen as risky with the unclear future of the pandemic and its impact on the economy.
This is why we seen stock and real estate investments rise. You add that to the fed rate cuts, and these are basically the only two mainstream investments that can be made.
Most investors into stocks aren't individuals like you and me who would otherwise go out dancing or go to bars. While there was a surge of individual investments, the bigger firms are attributed for creating the huge waves in the markets. Do you think that Warren Buffet/Berkshire decide to invest in retail stocks because he was bored due to not being able to go out clubbing? And when he buys stocks in something it outpaces what the entirety of WSBs does in puts/calls. And thats just one firm.
So, I find it hard to believe that the lack of entertainment (which was only really an issue at the very beginning of the pandemic, as baseball/basketball/football all carried on and plenty of games/shows/movies have come out) is the cause here.