It's a preference I have on role-playing games. In action games, hands-on tasks are what they are, a part of the game, but in RPGs the actions of your character should depend on your character's abilities rather than the player's. What should depend on the player are the decisions. What to do when, what abilities to use, if applicable what abilities to improve, where to stand in expectation of some nasty trap, what equipment to wear at what times, and so on. Those are decisions I want to make on behalf of my character, but I sure as heck don't want to carry those decisions out myself. I don't want to unbutton the top-most button, then the next button, then loosen a strap, then unhook a strap, and then unbutton a third button, just to change my outfit, but I don't mind aiming my bow in first person and ordering my character, through my mouse, to aim just a bit higher, just a bit higher, maybe a bit to the left, nope, back a bit to the right, there, fire! That's me making decisions and my character carrying out my decisions. My decisions has a great deal of impact on what target my character is aiming at. Whether he hits what I'm asking him to aim at should depend (IMO, obviously) on his archery skill, archery "perks", and possibly on raw character attributes as well. I get to see through his eyes and his decisions are made by my brain, but all actions depend on my character's skills.
This is very reasonable. But the lockpicking mini-game (for example) was created to simulate a feature of the game world that players can then interact with. It's not essentially different from being able to pick up a cup and move it around or riding a horse. It adds interactivity to the world. It makes the world more 'real'. The fact that it was implemented as a mini-game instead of as a 3d object is a reflection of the complexity of the interaction.
Should the difficulty of the mini-game be proportionate to the character's skill? Yes. You're never going to hear an argument against that. I don't think anyone who likes the mini-game has ever argued otherwise. And it's obvious they tried to scale it
somewhat to the character's skill because it does get easier. It's obvious that the design is inadequate (probably because they were afraid people would complain about it being too difficult) and the loss of the auto-pick option is unfortunate (probably removed to encourage players to take the lockpicking perks; ie. to promote role-playing) but that doesn't mean it can't be improved. Should people like me--who want to be able to participate in my character's actions--be prevented from using mechanics like this because other people--who apparently don't want to participate in the same way--don't like it?