That's somewhat inaccurate. You regenerate 0.70% per second of your total hit points outside of combat, 0.49% in combat. So if you have only 1% of your HP, at best that's about 140 seconds to get back to full health. (Of course enchantments/potions can make you regenerate faster).
I tend to agree with people saying that auto-health-regen is "catering to casuals" or "action gamers", but I think in this case it's a good thing. I did not find anything challenging or immersive about waiting/resting outside of combat, or spamming healing spells/potions. In fact, one could argue that auto-health-regen makes the game more challenging, in some respects, than previously. Previously, after combat you wait/rest, five seconds later you have full health. But now, the game encourages you to play on, even without having full health, so you run the risk of entering combat with less than full health.
Actually, I think the main reason why there's no point to not having auto-health-regen is because there's SO MUCH GOLD in Skyrim (and in all the previous games). And once you have lots of gold, you can buy heaps of healing potions. So every sort of character---warrior, mage, thief---always has an easy option to get to full health. All auto-health-regen means is that you don't need to buy/make a few extra health potions---which you could easily afford, if you had to.