I just find it odd that they stayed at the level of medieval technology for thousands and thousands of years, and then, in (I'm guessing) a few thousand years shot up, past our level, to a cyberpunk (again guessing) form of technology.
Er.
Firstly, medieval is more a cultural classification than a technological one. I'm not sure what makes you think they stayed at the same level of technology for thousands of years, or how you can judge the length of the fourth era, but technologies have been both lost and gained, some civilisations of antiquity having sprung up already advanced, which reduces the need to pioneer new things. See, for example, the Dwemer. Still, Tamriel seems to have gotten the printing press, new types of armour have been created by the Dunmer and magic has alway been considered a sort of science, and that isn't going to change any time soon.
Secondly, cyberpunk isn't a form of technology, it's a sci fi genre and an aesthetic associated with anti-heroes running through heavily urbanised futuristic dystopias. And yes, it would be silly for a shaking sugar-cat to be hacking a computer to get his next fix, so that ain't going to happen.