My biggest take away from the article is that the Otus used prices have come way down. Huh. That probably shouldn't be tempting....yet....it would be a bit fun to play around with it vs my RF 50 f/1.2. hmmm.
At least to me, the article almost perfectly surmises my point, even if one person's impressions are exactly correct, the Zeiss Otus 55 f/1.4 is better against 1) flare, 2) with vignetting, and 3) focus breathing. They also bring up color rendition, but that did not make the top 3 list for whatever reason. Seems to indicate resolution is a push. Yet, despite these, they still carry the EOS-R and RF 50 f/1.2 when they take a "second bag" with them for "easy" shooting when they do not feel inclined to use a "proper camera". Which I read that even to someone that previously owned and clearly prefers the Otus (with 5DRs), the RF 50 f/1.2 (with EOS-R) still meets their standards, at least part of the time.
There will always be people willing to pay extra for a specific feature.
I am making an assumption that whatever Zeiss does will have a similar 2x-3x higher price point, similar to the Otus vs "L" 10-15 years ago. Back then, the Otus was clearly better in a number of ways. Yet at that price point even back then with the advantages, I think only a small group of people actually made that investment. If Zeiss comes out with a $5-7k lens even with better flare, vignetting and focus breathing, I would not expect it to sell well. If they come out with a $2-3k lens that is better...then yes, I suspect it will have a reasonable, yet likely smallish (no-AF) market.