I haven't done Everest because of the O2 garbage and queues but I have done another one of the other Himalayan treks in Nepal. They are no joke. At all. Sure they're well marked trails, have been done untold times, and you can have a porter, guide, etc but despite all that you're at serious altitude, donkeys and yaks will knock you 1000m off a cliff, there are rock slides and avalanches, it's 9 hours up hill per day most of the time, and then as if that's not bad enough it's far harder on the way down. My knees are still pissed off about my time in the Himalayas and I didn't do anything as hard as summiting Everest.
Those of you trying to downplay doing it should give it a whirl. Might sound easy on paper but when you're up there you're basically giving your body the middle finger day in and day out and hoping it doesn't tell you to fuck off and kill you. Nobody is going to carry you to the top. You have to do it yourself.
For those of you who might do it one day definitely invest in having others carry all your gear and take it slow. I went way too fast and that is NOT the way to do anything up there besides when you get to the top or are going over the passes and need to get back down quickly.
These treks are not guaranteed. I don't know what the numbers are but I can imagine that many have to abort. Too many idiots underestimate it and go up there out of shape or smoking weed and then find themselves in a world of hurt.