Because harder raids means you have to think about how to deal with a mechanic. You are not "cheesing" a mechanic if you are able to think outside the box and deal with it. Other than exploits such as teleporting, it is good that people are finding ways to deal with mechanics that SE wouldn't think of (or else it would've not been possible).

Why wouldn't you do the easiest thing to do either? I'd argue when the "cheese" strat becomes well known, it would be stupid to not use it, if all it carried was benefits (in T2, enrage strat carried the con of having to wait ages, so for this reason IMO it was stupid to use unless you had no static). Time is valuable and in the hardest content you have to do everything you can to try to maximize progression while on a limited time restraint.