While many factors such as bad writing, bad art, and "Social messages" are a big part of why comics are in decline. I personally believe the biggest factor is the refusal of introducing new genres and storylines into the comic book industry. You have only one genre to pick from, and it's Superhero. That's it. While these superhero stories will have elements of other genres, you're ultimately forced to read superhero storylines when you pick up a comic from the Marvel and DC. The B List companies like Dark Horse and IDW do have some mix of genres in there, but it's the big Two that everyone cares about. And the use of connected continuity that goes back decades continues to alienate any new readers who want to get into comics when X and Y character are referred from a storyline from 20 years ago.

Manga has a huge variety of genres and stories to pick from. You're not stuck reading 14 similar versions of My Hero Academia. You can read Lucky Star, you can read Another, you can read Sailor Moon. All very different books from very different creators. Which are all very easy to pick up and get into without needing years of lore to make sense of anything. The Comic book industry was doomed to fail because it will never expand or attempt to change to the growing tastes of new audiences that want something different.

My take is that an entertaining industry (videogames or comic/manga) is gonna be always superior to the other one, specially when one is unadulterated stories straight from the author, without trying to shove ideologies and current political points down your throat.

It seems like people forgot that both videogames and comic books are both a tool for entertaining and escapism. People don't want to be preached in their free time, they just wanna play a videogame about shooting demons or read a manga about monsters and heroes, and turn off their brains for a while while enjoying a good story with actual good written characters. Because a character being non-binary does not make them a good written character by default, sorry twitter.