The initial release of Proton felt like magic to me.
I tried many games with Wine across many years, from versions well before Wine 1.0 to 4.0, I also tried CodeWeavers something (Crossover?) when that was a thing. A few games worked very well, for example I remember running a newly-released Civ4 almost seamlessly. But most games didn't. Some would be playable but with graphical or audio glitches, performance or stability issues. Others wouldn't be playable no matter what. Tinkering with dll overrides, wineprefixes and all that was often necessary.
Then Proton came and, almost overnight, the Linux gaming experience improved more than in the previous fifteen years of Wine-based attempts. A few years later now, my default expectation has changed to games just working on Linux, unless they use a rootkit-style anti-cheat system. Most games I played under Proton have worked with native-like quality, I could as well be running them on a Windows gaming rig. A few games worked with minor issues such as a few seconds of garbled audio on startup or slower startup. There's only one recent game where I had to give up on Proton, and that game is supposed to run well according to ProtonDB, I just couldn't it right on my system.
I haven't been able to find any info to confirm but I have a sneaking suspicion that Proton builds heavily on Codeweaver's Crossover. The vast majority of commits in the Proton repo come from Codeweavers employees
I think the biggest change was bundling (and funding the development of) DXVK which the Wine developers were too stubborn to adobt over their own wrapper.
I tried many games with Wine across many years, from versions well before Wine 1.0 to 4.0, I also tried CodeWeavers something (Crossover?) when that was a thing. A few games worked very well, for example I remember running a newly-released Civ4 almost seamlessly. But most games didn't. Some would be playable but with graphical or audio glitches, performance or stability issues. Others wouldn't be playable no matter what. Tinkering with dll overrides, wineprefixes and all that was often necessary.
Then Proton came and, almost overnight, the Linux gaming experience improved more than in the previous fifteen years of Wine-based attempts. A few years later now, my default expectation has changed to games just working on Linux, unless they use a rootkit-style anti-cheat system. Most games I played under Proton have worked with native-like quality, I could as well be running them on a Windows gaming rig. A few games worked with minor issues such as a few seconds of garbled audio on startup or slower startup. There's only one recent game where I had to give up on Proton, and that game is supposed to run well according to ProtonDB, I just couldn't it right on my system.