That is the monetization method that many newspapers use.
For example to comment on welt.de you need pay for a monthly subscription.
People want the feeling of getting heard. They want their opinion to be recognized. They want to actively take part in forming the public opinion.
It makes sense to charge for this, especially in the age of LLMs. Maybe we even ought to charge for it.
It is so easy to manipulate the public opinion now thanks to this new technology. So there has to be a barrier to entry that can’t be easily gamed.