It's not just making good movies, although the movies have to be good
Like if the Superhero movie being reviewed feels like it's more of the same, it'll be judged more harshly
Like I was going through the IW reviews and the ppl who were complaining felt like it was more of the same stuff...like previous avengers movies but just louder....that it wasn't like ragnarok or bp that 'offered a fresh take on the genre'...ragnarok had done a complete 180 on itself and made fun of everything marvel had previously taken seriously about thor...bp was celebrated for its diversity and social and political commentary... In that sense I think there is a fatigue among critics
When it comes to the general public, yea there's no fatigue yet. In fact the Superhero brand sounds like it's getting stronger. Like Marvel's increasing their social media following. In fact I think Marvels YouTube subscribers doubled after iw trailer came out. And then look at ant man 2 trailer which has 400 likes.. Etc