One can argue past pricing all day, but that's not relevant to the claim that the R was a "screw up."
Three years after introduction it remains a very competitive and high quality camera that was critical to the successful launch of the R series. I'm sure Canon would like to have more "screw ups" like that.
Price is highly relevant because it is the value that the R system provides that causes people to adopt it and value is based on features and price. The R launched at 2300, the Z6 launched at 2000 and the Z7 launched at 2600. At 2300, it was an overpriced "screw up". They dropped the price to 2000 about half a year later. You think that was Canon's original plan, or do you think that they realized they priced it too high and had to discount it?
After 3 years, it is not a competitive camera, unless you factor in it's reduced price, but then you say pricing is not relevant to this discussion, so which is it? I had hoped that Canon would have had something closer to the R5/R6 at launch rather than the R given it's experience in developing the EOS M system. I think the R and RP were stopgap measures because Canon did not have the tech ready. Also notice the wonky "R" and "RP" names that are separate from the more established 1, 5 and 6 series. Canon would have done even better if it could launch the EOS R system with a better offering than the R. Canon was also correct in releasing the f/2.8 zoom trinity in 2019, shortly after the R was launched unlike what Nikon did with mainly leading with their f/1.8 primes and f/4 zooms. So yes, I think it was the RF glass that sold the R camera. The RF glass was the strength of the EOS R ecosystem, not the launch camera. People did not praise Canon for the R for its higher price than its competitors, lack of IBIS, touch bar or ORIGINAL AF performance. I love using the RF glass, I never loved using the R.
I tried the R when it first came out. It was ok, it was not categorically better than my 5D4. I kept the 5D4 for another 2 years after getting the R, and I used both. I got the R in 2018 to use the RF lenses, and I got the lenses that launched with the R because I could find them at a discount to MSRP shortly after launch. Otherwise, I would have waited for the first price drop. How often are discounts offered from something that just came out like that (weeks after launch)? I used the R for portraits, and the 5D4 for travel (GPS and longer battery life) and sports. The R did drive the fast EF primes much more accurately than the 5D4, which is why I favored it for portraits. I replaced the 5D4 with the R5. The R is a backup to the R5, but I haven't used it except to take video (while I'm using the R5 for stills) since I got the R5. The R5 feels like the true successor to the 5D4 while the R felt more like a younger brother to the 5D4 (two years younger with similar tech and slower frame rates).