As someone that occasionally lvls a few characters to max and tries their bad specs in m+; believe me, its not just us.
I dont know why but Blizzard is spending the least amount of resource on the actual specs, their spells and power (balancing).
I could understand it if this was moba where you could just pick the next OP/Meta Hero and go ham with it but this is an MMORPG and we invest alot on our characters yet Blizzard thinks it is okay for some specs to be bad or weird at certain things and it makes absolutely no sense.
My suggestion?
Give up.
Go take a look at US forum’s 9.1.5 PTR thread. PvP gearing topic by far has the highest amount of demand and they are basically asking for what we had in MoP / WoD.
Will we get it? Absolutely not.
So do what i do. Find ways to farm alot of gold, buy tokens. Hoard them and wait to see if Blizz changes.