Yeah, I know what you mean.
Do you know how annoying Eviolite Sableye would have been? Also, with Mawile having already gained a Mega, Sableye netting a permanent evolution would have felt wrong.
Wait, wait. Firstly, I thought that the fifth generation had different themes; secondly, what would any of its themes have to do with its Pokémon's abilities to Mega Evolve?
I can see it happening. What about its design do you disagree with?