It is all to do with the veracity of involvement. Bryan Singer allegedly was not even on set for most of the shooting for Days of Future Past and by the time of Apocalypse it reached unsustainable levels, each whatever you think, had mountains more of creatives involved than either AVP film.
So yes unironically easier to not think about Bryan Singer making profit of it, because he was not the sole beneficiary or creative onboard, arguably never even the main one unlike the AVP films.
The AVPs in terms of creative input are made primarily by bad artists and bad people, Bryan Singer's one bad person, and a good artist apparently, amongst a crew of good people and good artists with as much if not more control over the commercially and critically successful X-Men franchise projects than he had.
He had input and produced X-Men First Class, but it was written and directed by Matthew Vaughn and Jane Goldman, who also wrote X-Men Days of Future Past and an outline for X-Men Apocalypse, Bryan Singer just directed the sequels.
Which got switched around in production, that meant it destroyed Matthew Vaughn and Jane Goldman's careful chronology from sequel to sequel, that's why X-Men Days of Future Past feels like a fully formed if slightly edited story and X-Men Apocalypse like a retrofitted first draft because that's exactly what they are.
I am not giving anyone a pass here. Paul W.S Anderson, the Strauss Bros, and Bryan Singer are all irredeemable because of a continuity of abuse in each case frankly.