Anytime a new follow list or relay list or profile metadata note is sitned, relays should delete the old note versions of them to save space
If you follow 1500 people that means every relay is probably storing 1500 notes but only using 1
Discussion
Counter argument to store last 2-3. Some apps can nuke your follow list.
#nukening
Otherwise, makes sense 🫡
If that is a consideration, the relay could detect nukenings and retain the longest such list just in case.
According to the nips, relays are not supposed to store the old versions so most actually don't.
some of the same nonsense going on with preferred relays lists. and many of them dont use nip05 as a primary authority for preferred relays.