Twitter was quite diverse actually (it might still be, I can’t say). You had the far left, far right, and everything in between on there but it worked somewhat because the algorithm kept people mostly in their bubbles unless they went seeking it out.
Unfortunately there are very few open review projects and none that people have tried to actually integrate into one of the OSM apps. It makes me rather disappointed as finding businesses and checking reviews is one of the most common uses I have for Google Maps and yet OSM cannot replace it.