@poVoq @ndr this will surely grow a lot, if you look at other activity pub compatible systems you'll see a huge grow, it depends on the retention of "old" post and media, if you say just store all for a year you might keep it smaller, but if you want to replace #Reddit or so it would be better to keep stuff a bit longer, but then on the other hand the #Fediverse is probable not meant to store stuff for long term.
On my Friendica node I have a rather short period to store foreign posts and media, and my storage is only about 47 GB, most of the media is stored in the database as well (easier and faster to backup, much slower to retrieve) and it is a single user instance with just a handful of bots besides the account I write from.
utzer [Friendica] @social.yl.ms Mitglied im asozialen Netzwerk
Ursprünglich aus dem Rheinland, aber aktuell ca. 600 km weit verschoben.