I would say it is a stretch. there is a certain level of complexity below which the game can't go, before it ceases to be an ES game except in name only. That level is of course a matter of personal opinion. All features are somewhat superfluous, fair enough, but a certain amount of any features is required and expected.
Do perks do what attributes did? No. Will the perk system mean as much differentiation between builds is possible as was the case with attributes? I would say yes, more so, and choices are required now. One level of depth is gone, a different one has replaced it. Same with armour. There were more choices with separate pieces than there will be with extra types. Some lament this, obviously, they want to mix their steel cuirass with any greaves or trousers. Others however, are glad there will be more than one look to the steel cuirass they can choose, and are getting a choice they didn't have before. Are the first group right because they have a greater number on their side? No, it's opinion.
Same with spellmaking vs. having to make tactical choices regarding what to equip, and which one element to use for destruction spells against a given enemy. A lot of choices are gone, but choices made in preparation, in safety; now there are choices required, in the field, in combat. Who is objectively to say which is more 'hardcoe'?
18, or 10 or 40 skills allow choice, the reductionist hyperbole says a system that doesn't allow choice is the same.
The reductionist hyperbole just asks when less choice will stop being acceptable.
Bioshock 2, for instance, is what I imagine a heavily "dumbed-down" (or streamlined if you prefer) version of TES might look like. It essentially has magic, there is a choice of weapons, you have health and magika, and there are even ways to increase your skill level in any of these given areas. There are even attributes working behind the scenes (even though you have little control over them outside of Gene Tonics). It also has perks and pseudo-perk trees [gene tonics] and you can even combine plasmids like Skyrim magic. With these options, there are actually a large number of ways to play your character. There is choice here.
That said, even if one were to add some of the basic TES elements it's lacking (make it less "on rails", add towns and open exploration, character creation options for races and race starting perks, a visible inventory system and clothing choice), it would still be an extremely
dumbed-down streamlined version of the game. The question that people who hyperbole the decrease in choice ask is, "Is this acceptable?"
Bioshock 2 is a very fun game, in my opinion. I played through it twice, each time with a totally different plasmid and weapon focus. I'm sure they could make a fun game out of
"Bioshock but with swords instead of guns and magic instead of plasmids".
Who is to objectively say that that game would be worse than, oh say, Morrowind? No one, but what can be said objectively is that RPGs are generally defined by the number of roleplaying choices they give you. Assuming equally accessible controls and ignoring the storyline for a moment, the objectively "better" RPG would then be the one that gives the player the greatest amount of roleplaying control, or choice.