AMD's OpenGL issues aren't just speed related. Many including myself have experienced quite a bit of instability as well, driver crashes or even BSODs. I've had this occur on different AMD cards from different PCs. A problem that disappeared when I swapped in an Nvidia card instead. The problems are not inherent limits with OGL itself. Many well respected emulator programmers hate AMD drivers as well. Nvidia's cards work just fine, and they haven't made any proprietary tweaks that would stop AMD from fixing their shit. No emulator author is implementing proprietary crap like Gameworks either. Vulkan IS supposed to be better and lower level than OpenGL. AMD helped create it, so no excuse for it not to perform well on their cards. Vulkan was initially expected to make a big splash in the mainstream, though this has largely not been the case outside of id Tech games. This in spite of many prominent game engines such as Unreal 4 supporting Vulkan. Even the emulation scene hasn't universally jumped on Vulkan. Dolphin was quick to do so, and I believe PPSSPP eventually got it alongside RPCS3. Some Retroarch cores support it. But Citra, PCSX2 and Cemu still only support DirectX or OpenGL.