Let's say, the data will stay forever as long as someone is running a node... As soon as all witnesses stops, everything is lost
Hive is way better than any web2 platform, the problem is, people want to try and be content creators, famous ones, and you can't do that on hive... Papers, average people talk about TikTok, Instagram, Facebook, no one knows hive so influencers are just there, would need a big influencer to promote and use only hive to attract people
If people stop running a node it just means blocks stop being produced and the chain halts, doesn't necessarily mean the data is lost if it's still on some harddrives/ssd's of older witnesses.
Oh right, you need witnesses to stop and format all hds