Originally Posted by eternaltransit

Indeed - it can be either way. The lesson I think is that you can never know! I was once on an overbooked by 20 Y flight, there I was expecting an op-up but no beep. I later find out that they lost 30 people in connecting

I think it is just not worth stress of trying to set expectations on how many other people there are in the cabin with you. The only way you can do that reliably is if you have staff friends who can reliably check loads for you. Otherwise it's just hassle - book your flight in the class you want to fly and don't let expectations get away with you