I often see not 'just' AGPL, but AGPL+Source Attribution Policy (if you contribute to the main repo, you must assign copyright to the owner), and specifically around network/web oriented software.

This combination is pretty antithetical to the 'spirit' of open source (and especially 'libre software', which AGPL is supposed to be) since it basically ensures hegemony on any commercialization ecosystem to the original developer, unless one manages to create a 'leading fork' where contributions land, since only the original rights owner (who also gets the rights to the sum of all other contributions) has the legal means to commercialize (i.e: provide commercial hosting around) any extensions above and beyond what the community develops.