I run a page with over 150K likes (all real) and I usually tend to get 3-4K likes on a photo, occasionally even more. The last 2-3 months were horrible, I seriously can't even reach 500 likes on a photo, and in my opinion and uploading even better content lol I don't spam a lot, neither post very rarely. I also post on hours where people are most active. Nothing. Other big pages are unharmed but mine. I recently tried running an ad for $9 and it was fine. I got around 2-3K likes on a photo and the reach was better. But when I stopped running ads, everything went back to that horrible state. What seriously can do? I bet if other pages which are similarly popular to mine, uploaded the same things as me, they'd get 10x the likes of mine.