Group chats are basically the Circles that Google+ saw the need for but could never get fully set up. A lot of people don’t want to share personal updates and photos to a broad swath of friends and acquaintances.
Meanwhile Instagram and Facebook keep evolving. Facebook is turning into a weird Reddit for older people. Instagram is turning into a hipper LinkedIn, where artists, musicians, and local businesses share career and business updates and advertise their wares.
Too bad because other topics like woodworking and mountain biking we're interesting and less... provocative, but that's not good for Instagram.
The algorithim is optimized for "engagement", and therefore optimized specifically to trigger addiction as quickly and effectively as possible. The lower level softcore porn and rage bait and brainrot memes are what triggers addiction in people prone to it.
It's exactly the same situation as slot machines. They are made by the same companies in many cases that made some of the best and most fun arcade and video games. But if you aren't prone to gambling addiction, they aren't fun, because they aren't optimized for fun, they are optimized for addiction. The same triggers and stimuli that are most effective at triggering addiction behaviors are LESS effective at being "fun" to non-addictive people.
"The algorithm" is literally not meant to feed people what they want. "The algorithm" serves only the interests of the company, which is to efficiently keep eyeballs looking at a feed in order to sell ads. Giving most people what they want is genuinely counter to that.
I have found out that the algorithm will adjust itself relatively quickly if you don't click on stuff (at some point it decided I was into foot fetish and it disappeared quickly). With that I get stuff about philosophy, math (memes), science and technology stuff with a lot of animals videos.