This makes me sad. There are boatloads of great material out there in all those categories. If you're not seeing it, you're not looking in the right places.
I'm in my forties, my friends of the same age often make the same complaints as yours and all of them use the mainstream channels to discover/listen/watch culture and art, and that's where they are all going wrong. If you rely on the mainstream for your culture, you're going to get the lowest common denominator entertainment. The stuff that's meant to appeal to everyone, that's safe and bland to generate the most revenue. That's obviously going to be the case in every category.
If you go deeper than that and use less known channels, you're going to find some incredible stuff. If you look for comics from Marvel or DC you're going to be disappointed. If you reply on the mainstream charts for music, you're going to be disappointed. If you look for films in the multiplex you're going to get the generic stuff.
I've discovered some excellent bands in the last 3 or 4 years that never ever bother the charts or radio. They're new, exciting and putting out great work. They're touring next year and I'm pumped to see them.
I use a number of subreddits to find out about bands, films, tv and such, and there are lots of people happy to recommend great things.
It's like The A-Team - you got to find them.
Regarding even the mainstream stuff though, there's good material out there: The TV comment is particularly confusing - especially as it's universally agreed that we're in a golden era of TV making. I mean, just in the UK alone, you've got: Fleabag, Broadchurch, Killing Eve, Peaky Blinders, Black Mirror, I May Destroy You, Staged... to name but a few. There have been some excellent films out in the last 5 years also - Relic, The Sound of Metal, Mogul Mowgli, Nomadland, Three Billboards Outside Ebbing Missouri etc.