yeah, i dont consider myself anywhere above intermediate at best, my lifts are average for a gym goer natty or not, its a fine line tho before average lifts become above average. I think most trainers with dedication would reach where i am now, its where you go beyond that level that matters.
My own opinion is that an OHP of 100Kg bench of 120kg squat of 150 and dead of 200kg, is just about the starting point for a gym goer to be out of that 'beginner' phase. To some degree i think this is bodyweight irrelevant too, these are about the weights where the body is under pressure from the sheer mass. 150KG on my back still feels damn heavy despite the fact i can rep it with some comfort. A 120 bench still feels strenuous to take off the catchers despite it being close to a warm up weight. These weights are all at or above the typical human bodyweight give or take around 10kg's and at this point the ability to move them becomes about something else, something the body is not programmed from birth to ever do. Once you exceed this natural barrier, imo, you move into the intermediate class. Not until you are in the competitive weights range of 50% or so more weight do i feel you class as advanced. Thats my rating anyway.
It depends on how you define these sort of things. I think it's too problematic to start defining your level of lifting in terms of hard numbers, as this doesn't take into account bodyweight.
Defining advancement in terms of multiples of bw lifted is a bit better for obvious reasons, but then you run into some problems comparing very heavy lifters with very light lifters. You also will have some problems with people that are just very genetically strong right from the beginning. Everyone's heard of some guy that walks in a deadlift an insane amount of weight his first time ever. Is he more advanced that the guy that has been working hard for 5 years yet is still pulling 20kg less? Who's the beginner there?
I've always preferred to define beginner/intermediate/advanced lifters in terms of progress. If someone can walk in a lift heavier every single time they attempt a lift, without any sort of periodisation (etc) then they're at a more beginner level. If you're PBing 3 times a week for months on end, you can only really do that as a beginner. Once you start needing to have light/recovery sessions you start moving into intermediate level. PBs come a little fewer now, maybe once every week or every other week. Advanced lifters are the guys that may only PB a couple of times a year at best (assuming consistent training).
Anyway, that's how I learnt it.