I think you do see it, you're just conveniently ignoring it. Throwing piles of cash at a developer to limit a customer's buying options to a single platform is anti-competitive. If Steam had been doing the same all these years, it would indeed be the monopoly you're claiming it to be, and Origin/uPlay/Battle.net/EGS never would've existed because they'd all be outbid for their own IPs.
How have you not seen a commitment to it? There are tons of adult games of all types available on Steam right now, they aren't in the least bit hidden unless you choose to hide them. OTOH, we haven't heard anything whatsoever from Epic on censorship.
Again not a Steam-only thing, I've never heard of any storefront allowing resale of digital products. That would require digital products to be priced the same as physical ones, thus removing much of the appeal.
You're right, it's meaningless because Epic ignores the supposed "problem" of a 30% cut on all platforms except for Steam. They also conveniently ignore the keys system from which Steam takes a 0% cut. In the end, Sweeney is just angry at himself for not seeing the value in the PC gaming market much sooner, and he's chosen Steam as a scapegoat so that he doesn't have to take responsibility for all of his own poor decision-making. Don't be like Sweeney.
I am sticking with the video distributor, talent scout, general notions of contracts to use patents, general contracts to be the distributor of [clothing line] and on and on and on analogy here. I can't see epic stumping up some cash to make their offering more attractive by virtue of having more content be something to deem some flavour of anti competitive. Or if it is somehow anti competitive then it is the acceptable aspect of it, which is an odd term to coin but whatever.
Epic making a committent not to censor would be a nice thing. Until you do some censorship though, much less do it in the position of monopoly...
If Steam is installed on the vast majority of potential gamer PCs and where vast segments of the market almost exclusively operate then the lack of exposure (which Epic appears to want to address in their deals) becomes a factor. It is somewhat like offering paypal -- they cost a fortune relative to other means and are a horror to work with but if it is what a significant chunk of your (potential) users operate with in a do or die kind of sentiment then you get to consider whether you want to play there, this despite there technically being a thousand other ways you can take payment.
Steam does not have to do anything here as they are so far ahead as a market leader -- it would be like Microsoft worrying that I am developing an OS and office program myself, which is to say "who?" is probably a perfectly acceptable answer from their otherwise very clued up business intelligence division.
There have been several services floated with either DRM free offers meaning de facto resale/gifting/disposal of your choice is implied, there have been DRM services wherein you can lend people keys to access the service and thus if that appears in public it is said to be lost and gets revoked, and that it is at all conceivable (never mind trivially physically implemented on current systems -- the whole gifting thing just needs the "is used?" thing turned off). Various courts, including high level ones, have ruled that resale must be an option provided.
Similarly it would not require prices to match physical ones -- the lack of necessary infrastructure/upfront costs seeing to that one. Chucking something on a pay to play CDN is far far far cheaper than even a modest DVD pressing session, and you are probably going to have a CDN for the updates too.
It would also solve the "not available for sale any more" problem the same as physical largely has.
30% for a payment provider and CDN for relatively low size-latency/speed minimal concern but high value product? Seems like a perfectly valid thing to have issue with, and a front to try to compete on. 0% keys might influence the final cost calculation a tiny bit, though if it ultimately boils down to still installing Steam then I don't see how it is all that different as a slip in via the back door and get people using it ploy that you seem to find so offensive.
I would be kicking myself too if I had enjoyed the position I did and not jumped, and if Steam are the king you take aim at the king if you want to be the big dog.