Nope, Bryan's comparison is not valid, because Canon changed the way they plot MTFs in 2018. The big clue is the old format has 8 lines and the new format has only 4 lines, you cannot compare the two. Canon Japan has the current version MTFs for all the lenses, but for example Canon USA didn't bother to update the old ones.
Details from Canon on MTF charts here.
Here are the MTFs compared as apples to apples (new lens on top):
The lenses are pretty similar in terms of MTF at the wide end, the EF is very slightly sharper, contrast (black lines) is similar. Resolution (blue lines) is noticeably higher at the long end for the RF lens.
I don't plan to swap my current EF 11-24/4 for this lens. The drop-in filters are very convenient and a big advantage for me. I used a 10-stop ND gel with the 11-24 before R bodies, they're a bit annoying to use and there's no CPL option (useful for cutting reflections on glass/water). But it does look like a very nice lens!