I have a Shimergo bike with 3x11 Athena Ergos running an SIS 9-speed rear and MTB FD. It works. But that's old news.

I tried via Googling to find info to build an updated table, one that would include all the 11-speed systems now out there, not having anything of my own to actually measure. What I found was a lot of conflict, errors, and lack of info for 11-speed stuff newer than Ergos, epsecially on the MTB side. Errors on cassette spacing in one article will turn into errors in pull ratio in the next article which turn into errors in cable pull in the next one, all without attribution. Actual measurements seem scarce.

You will find all kinds of hacks out there in the MTB world, people running mixes of 10/11 stuff, SRAM/shimano hybrid systems with spacers on the RD pinch bolt to modify the lever arm. This becomes relevant to road bikes because the SRAM brifters are somewhat cross compatible with their MTB stuff.

There are clearly people like WolfTooth who have done the math and experiments.

I have a theory that the new 10-speed Tiagra 4700 brifter should shift an SIS 8-speed rear and I'd love to hear if anyone can try it.