Sure, but at least on reddit, if you don't like a moderation style, you can set up a competing sub-reddit r/fitness to r/advancedfitness, or r/weightlifting to r/powerbuilding to r/bodybuidling to r/naturalbodybuilding - the opportunities are endless.

No such alternative exists on NextDoor. Don't like the content or moderators? Your only choice is stop participating. I have no idea why NextDoor thinks that is good for their business model. Over time the site will just be populated with Karens.