Last time.
It is a single player game. If someone wants to enchant all their clothing, armor, jewelry, and weapons, it doesn't matter. In *your opinion* it is abuse. For someone else, it could be the most fun aspect they've created in their game.
It does matter. Bethesda's going to try (not necessarily succeed, but try) to make every archetype equally viable so that someone playing as a magic user isn't at a severe disadvantage when compared to, say, a combat class. Otherwise the game could easily end up feeling uneven and even unfair for certain character types. That means that allowing for one specific archetype to have a single skill that more or less completely breaks the game and allows them to bypass the difficulty entirely not only means a significantly higher amount of work needs to go into balancing the overall game and tweaking other character types, but also that other skills and abilities need to be tweaked and buffed to bring them up to par with that one. All of that means significantly more work for Bethesda's designers at best and an easily exploited and poorly balanced experience with uneven skills and a wobbly difficulty curve at worst.
Single player or not, balancing is still important and any decision they make to influence the viability of one class is still going to influence the others.