'Every' is a bit of an overstatement. I subscribe to about 100 subs and they are all non-political and not echo chambers at all. I mostly stick to subs with <300k users and many of them only allow text-based posts and promote balanced discussions. It all depends on who is moderating.
If I feel like a sub is starting to turn bad I just leave. There are hundreds of new interesting subs being created every week. THERE is where the value is.
99% of everything is crap - that truth holds everywhere - you just have to find the 1% that's worth it. For that 1%, there really isn't any other site with that level of discussion and community. For sure some Discords offer it, but I much prefer the forum format.
Here are some examples that I like personally. You should of course find your own.
https://www.reddit.com/r/howdidtheycodeit/ - people ask how stuff in games was coded
https://www.reddit.com/r/ArchitecturalRevival/ - photos of horrible modern buildings being replaced with beautiful older-style ones
https://www.reddit.com/r/etymologymaps/ - maps showing how languages evolve
https://www.reddit.com/r/whatisthisthing/ - people asking what random items are
https://www.reddit.com/r/ATBGE/ - things that are ugly but show incredible technical or artistic skill
https://www.reddit.com/r/OutOfTheLoop/ - people asking about memes/happenings that you might have missed, and providing excellent summaries
+ your niche subs for your local area / favourite TV show / musical instrument / sport etc, although some can be a bit too 'echo chambery' if too large.