The purpose of these milestone reunions (in my limited experience) is for the people who were somewhat popular (not coincidentally the same people who are arranging the milestone reunions) to show that they have become moderately successful to the people who were not popular then and aren't successful now.

To paraphrase Steely Dan, we need a reunion for the losers.

Or as the Kinks would say, the misfits. https://youtu.be/CiOwasZNL_U?si=jOActh-rv50MkZwN