To proper roleplay you have the game to provide a definitie infrastructure and adequate response to your line of action.
As such Skyrim is not a roleplaying game. It's stat based, mostly for combat action, but that's all.
You cannot roleplay in Skyrim, at best you can LARP (meaning you can impose your own self restrictions, perform certain optional acrions but these won't prompt any reactions from the game)
your opinion? I'm pretty sure I can role-play
Debateable.
In my experience I've seen two types of roleplayers frequent these kinds of forums. One I suppose would be called traditionalist and they actively name the people who roleplay in Skyrim Live-Action Roleplayers.
The difference? In Skyrim, you can't really roleplay decisions. For example there's a thread on the front page complaining you can't be a Companion without being a werewolf for a time. While a traditionalist RPGer would ask himself if his character would agree with being a werewolf and respond based on that character's personality, morals or honor code, Skyrim doesn't even give you this choice. Infact Skyrim seldomly gives you any choice at all, and it's even more rare that the choice is truly meaningful or has some form of influence on the world around you. In that sense, you can't really take each step of each quest in and ask yourself "what would my character do" because Skyrim doesn't give a [censored] and forces you to complete the quest it's way or don't complete the quest at all.
Thus, the roleplaying in Skyrim is rarely about how your character -actually- interacts with the world, but how you use your imagination when playing him. Maybe you've decided your character loves beer and thus you constantly buy bottles of it and drink it almost nonstop, maybe you've decided your character is a farmer so you spend a lot of time harvesting crops and selling them for gold. That's great and all, but again that has little to do with you interacting with the world (or in this case, the NPCs) but rather you're just imagining purposes to items and locations. Your beer-guzzling warrior and your fruit-eating warrior will still solve the quests the same exact way and they'll still leave the same exact marks on the worlds, you're just pretending small differences that really leave no noticeable marks on the world.
So yeah, for a good percent of the population, the roleplaying possibilities aren't considered good
enough because you can LARP in literally almost any game you buy, but Skyrim offers little choice or meaningful interaction amongst NPCs.