Unarmoured wasn't the only problem for mages, you often had to carry a considerable number of mana potions to survive in fights. There was always the balancing problems, one being armoured players always had more enchantment slots available than unarmoured. So between a armour class that didn't work, plus having far less enchantment slots, the game was very unfairly balanced against robed mages. So when Oblivion came along; there was the hope of resolving all these problems in the sequel. In fact the developers made all sorts of promises to assure mage fans that their concerns were being addressed.
Then Oblivion arrived, and little by little I got that sinking feeling that mages were being neglected again.
They had resolved the mana problems, giving us a suitable mana regen so that fights didn't become potion drinking fests, that's something good they did. What wasn't so good is their promises to address unarmoured hadn't gone nearly as far as people hoped. They had removed the unarmoured skill completely, claiming the perks of unarmoured would come from the disadvantages of wearing armour. What they failed to inform us prior to release, is that almost all the downsides of wearing armour would be negated later in the game. If you were wearing clothing mid to end game, you were worse off than a armoured player. Some skills worked 5% better, but it came at a cost of 100% of your defence. Both light and heavy armour got the maximum defence in the game, armoured players were left with 0.
As if this wasn't bad enough, Bethesda seemed to have gone out of their way to make some aspects even worse. They made it so that you couldn't wear armour and clothing at the same time, which was a step in the right direction to resolving balance issues; regarding the number of enchantment slots available. However, there are less clothing enchantment slots available in Oblivion than Morrowind, items like gloves didn't even exist in Oblivion. A lot of clothing were merged together, so a multi item outfit only represented a single enchantment slot. In addition, since they removed enchantment quality; that entire outfit was only as good as any single item.
Then to add insult to injury, as if to show robed characters were seen as second class citizens, they weren't allowed in the arena. They showed a robed mage on the arena poster, but you were disqualified if you weren't wearing the arena's light or heavy armour.
Over the last two games, the message Bethesda has been sending out has been consistent. If you want to play a mage, play a battle mage. Their vision of players is of an armoured hero throwing fireballs with one hand; before pulling out their weapon for melee. They don't want you to play a pure mage class, try to do so; and you will be worse off.
I can only hope the situation will improve in the next game. But given the trend, I somewhat doubt it.