I'm not a fan of reddit. Their horrible moderation structure aside, I blame it at least partially for the demise of all the niche forums that used to be scattered across the internet. These forums often had experts in the topic, and included shit that reddit bans like WTB/WTS forums for guns.

Regarding the idea of paid subreddits specifically, it's just part of the further enshitification of things. "Hey this free thing is popular, how can we monetize it?" Is the epitome of rent seeking behavior that characterizes this era of capitalism.

In this case though, I think it's doomed to failure. Unless they're going to aggressively stamp out free subreddits that cover the same topic as the paid ones most people are just not going to go somewhere and pay to get the same thing they're getting for free. The only people this is going to interest are those who hate that their own personal echo chamber is periodically invaded by strangers who don't share their beliefs.

If it's worth their money to pay so that they don't have to periodically ban the newcomers they don't like, then whatever.