Would you be prepared for example to pay £1/$1/1euro per month
If there's a central party to pay to, I'm not so convinced it's decentralized. It instantly makes me think it's only using "decentralized" as a buzz word.
For a truely decentralized social media platform, I imagine I'd have to download all information and store it locally. That won't happen for $1 per month. So I won't pay for it. It also helps I don't use social media, and I'm pretty convinced by now we'd all be better off without them anyway.