I am not convinced. They should just finish the fitting/kerning. Seems like a fad more than anything else.
In the screenshot, if you were to see a properly fitted proportional version of iA Quattro, you'd ditch iA Quattro. But that comparison is not presented, I don't think they've tried making a proportional version of it.
It's like this: A) Here is an unbaked cake. B) Here is a half-baked cake. But, the argument they are making is B) is better than C) Fully baked cake. No fully baked cake is presented for evaluation.
You can't use Nitti Grotesk, a cookie batter, to make an argument here either for a fair comparison. It's an entirely different thing.
In order to do a proper comparison, they should finish the kerning job and present their arguments fairly and squarly.
It needs a 3rd line "iA Writer Proportional". Looking at the word "next" in iA Quattro, the fitting looks really bad which is a known trade-off in monospaced typefaces, but not an excuse to leave it like that in a proportional typeface.
This stuff is like nails on a chalkboard to me. It is extremely unpleasant :-) It makes me appreciate good typefaces more, my favorites being anything designed by Matthew Carter. Legendary: https://en.wikipedia.org/wiki/Matthew_Carter
In the screenshot, if you were to see a properly fitted proportional version of iA Quattro, you'd ditch iA Quattro. But that comparison is not presented, I don't think they've tried making a proportional version of it.