I'm enjoying Season 4 so far, but it does feel like the writing is on the wall for the show, and I think Eric Kripke has made the right decision to cap it at 5 seasons. There simply isn't enough longevity to keep it going beyond that. Good shows know when to end.
Hopefully with the end in sight, we'll see some braver decisions towards the end of the season. Can't kill off Homelander since Anthony Starr pretty much carries the show, but everybody else should be fair game.