http://bugs.winehq.org/show_bug.cgi?id=58671
--- Comment #6 from Zak user.pecheniok@gmail.com ---
How are you launching it?
Just doing a wine Sonic3D.exe in the terminal (I have a separate wineprefix with the vulkan renderer enabled, but that should not matter)
Proton may patch wined3d and the other files so may differ from vanilla wine to fix issues.
However for Sonic3D.exe, even GE-Proton has broken FPS suggesting something major enough changed that it propagates even through all the GE-Proton patches which normally resolve these types of bugs.
Also, I just retested on wine 9.21. You were right, the situation is not as bad as on wine 10, however, there are some severe fps drops at certain points that are present in wine 10 as well, and also a lot of weird stuttering. This is weird, because when I was testing for that bug report you mentioned, wine 9 was running worse than 10, but I'm not sure if I was testing that on X or not because wayland is sometimes 10-15 fps higher with that game.
Just retested on 10.0 rc 3 in wined3d before replying. I was kind of shocked, but at least on wayland, it runs at an almost flawless 60 fps with no stutters. Sometimes the hub drops a frame or 2(or more), unlike 8.21, but there are no frame drops in a specific spot both 9.21 and later versions of wine 10 struggle with. You mentioned the game crashing on 10.1, so I think the problem with the performance was introduced there. I will update the appropriate bug report with that. However, this bug report is specifically about problems with the wined3d Vulkan backend, so maybe we should discuss anything related to performance with the OpenGL backend in the other bug report you linked.