this perfectly sums up the current situation imho, but is that number is really the limit? after so many hours of theorycrafting, i am very sure that number can be at least 6 for each class if a proper balance is applied. sure there will always be a meta, there will be always one "strongest" build but this isnt a big problem. having 6 builds to be able to clear at least GR 70 will do enough. and with all that diversity im sure there will be exciting multiplayer sessions in every season where creativity of interesting comboes will shine. there wont be some few obvious meta that people know before even a new season. seeing meta shapes slowly in every season, creates an excitement factor.. at least player slike me would be way more excited thats what im sure.
If this was 3 years ago it would be more of a thing. As I stated this game is maintenance mode now, don't expect anything. It took them a long time just to balance LoN and each class sets to somewhat be comparable to each-other... trying to make everything great without causing another ability to over-shine sounds like a big undertaking that a game in its early life cycle would attempt to achieve.