Shitty content is definitely not just Netlix issue. A lot of content from many different providers is simply bland now. The issue is that production companies rely on algorithms to decide what will sell. "People liked this show about ghosts and this show about pirates so let's make a show about ghost pirates". That being said, many original shows are still huge success so they still try to branch out and try new things. So yes, there's more and more mediocre, bland content but it affects all platform and all content, not just Netflix.

For me personally fragmentation is the big issue. If someone made "Spotify for movies", where I could watch literally all the shows on a single subscription, without ads, with good UI and interoperability between platforms I would pay for it. I will not pay for 10 subscriptions to watch one show from each one of them. I think Netflix as a platform is fine, it's the market that shitty.