i didn't check but i believe the major part of the extra mile is fixing 1000s of tiny little bugs that break games. it should be possible to verify that by looking at the wine changelog. the rest is creating a smooth experience downloading and running games. smoother than any alternative (like playonlinux or lutris)
Wine has worked surprisingly well for a long time, well before Valve got involved, although compatibility was never perfect of course (and still isn't!) I don't think they had to "fix 1000s of tiny little bugs that break games". Codeweavers has been selling commercial Wine-based solutions for a long time.
It's easy to offer a better experience if you also own the actual storefront; that was kind of my point.
And as I said, I'm sure Valve contributes; but describing wine as some sort of semi-usable half-working project before their involvement is rather inaccurate.
describing wine as some sort of semi-usable half-working project before their involvement is rather inaccurate
i disagree. wine worked, but many games didn't. fixing that is mostly valve's doing. and in my opinion the wine experience is still inferior compared to steam.
the problem is very much one of perception. 90% of the work that went into wine was already there. but the remaining 10% of work that was missing make up 90% of the impression of how well it is working. (the numbers are made up, but i hope you get my idea. it's the general linux desktop problem. the desktop is functional and stable, but the impression of it isn't because of a few small issues that just seem to bother many people)
so by attacking these remaining issues, valve is making a significant contribution.
i think it is also important that valve is able to apply patches before they make it into wine, because that means these patches see way more testing than the wine project probably would be capable of on their own. which is another reason that makes vales work significant.
I used wine for many years. "Semi-usable half-working project" was entirely my experience; nearly everything I tried to run had at least one weird bug.
The proton work is open source (and readily installable without using the storefront), so you can actually just look and see that they did, in fact, fix many little bugs that break games - perhaps only many hundreds, rather than thousands.
Have you actually used the commercial version? It's relatively stable and QAed and you can get support from the Wine developers, but it lags the open source version by months. You're not getting the latest compatibility fixes or performance improvements with it.
nevertheless the commercial version must be of use to someone by addressing pain points that other users don't have. and i wager that it is exactly those small issues that don't bother others but that matter for people willing to pay for it.
Theorycrafting here, but wine and proton will make it pretty easy to decouple Steam platform DRM.
It should be noted that it's perfectly possible to release your game on steam in a way where the steam client doesn't even need to be running in order to launch the game. The choice to tie Steam's service into the ability to run the software you purchase /seems/ to be a decision made entirely by the people publishing their games.
If that's the case, you should really be more concerned about that behavior rather than Steam's DRM existing. Don't buy games whose behaviors you disagree with!