IIRC the original Xbox has even worse emulation, to this day, despite being infamously close to a stock PC.
What makes RDR’s emulation struggles noteworthy is that it’s a highly desirable game that still took ages to unfuck. Most nightmare cases for emulators seem to be random D-list titles. Pinball Fantasies on Game Boy had incomprehensible crashes, early and reliably, for no discernible reason. True Crime New York on Gamecube was a white whale for Dolphin despite being absolute garbage.
RDR was a huge deal for its own sake - and it ran bad, looked worse, and stayed that way for a while. Back in the day it was common for emulators to only work properly for big-name games. NESticle and SNES9X absolutely cheated to run major titles. Early N64 development was nothing but. So having this killer app refuse to work, year after year, was a lingering presence in people’s minds.
Finally getting it working, only to have a nearly painless alternative drop, is pretty goddang funny.