Yes. Despite this being a super versatile setup, it still cannot cover everything. As you said, even machines of the time period can't do it for one reason or another. But I think the range covered by this setup is the widest I've come across so far just by counting what works vs. what doesn't. All the OSes, and all the generations of games and programs along with them.
So now compared to 10 years ago, I guess I'm even more convinced about it than before (after I've come across many more period-accurate builds).
The major period not well-covered by this is XT-era software, which is tough to get right even on anything newer than a real XT (super speed sensitive) like Digger, Bad Dudes, Might & Magic 1 to name a few.
I haven't tried SBEMU and its derivatives against the cases that fail with the YMF744. But if it works, then that makes for an awesome patch to the small hole left by the PCI sound card. The game I'm most interested in is Crusader No Remorse/No Regret. I'll try it and report back here.
I'm not a big fan of relying on emulation solutions though, that's the whole point of using the YMF744 (hardware OPL3).. but I'm ok with SBEMU to cover for SB16 games like Crusader and Extreme Pinball where everything is mixed in software anyways before being sent to the hardware.
Turbo XT 12MHz, EGA, MFM HDD
Intel 386 DX-33, Speedstar 24X, SB 1.5, 1x CD
Intel 486 DX2-66, CL5428 VLB, SBPro 2, 2x CD
IBM BlueLightning 100MHz, CL5428, SB16, 4x CD
Intel Pentium 90, Matrox Millenium 2, SB16, 4x CD
HP Z400, Xeon 3.46GHz, YMF-744, RTX2060