I don't mind people comparing such projects against Anki, this is natural since Anki is quite dominant in this space, but I feel like every criticism of Anki on that list was either highly subjective, exaggerated, unfair, or outright wrong and unkind (in a "one does not climb a ladder by throwing others off it" manner). Not saying this is what Fernando intended to do here, but his sharp opinion does come across a bit like it here.

Personally, I find the interface is extremely functional; the ability to have deck hierarchies to be a massive feature, not a bug; the WYSIWYG being the default being obvious given the intended audience, but one can still easily edit a textfile and import it or edit in html mode directly if desired; converting something into latex math is as simple as enclosing it in "[$] ... [/$]" and hardly the nightmare it's portrayed as; and finally potentially hacky plugins is a feature, not a bug: occasionally you have a very specific problem and some kind soul creates a solution for you, which may be functional but not the most aesthetically pleasing. That's fine. Anki is a bazaar, not a cathedral, and plugins have ratings and reviews which you can consult if necessary.

I have tried many different flashcard solutions, including hacky text-based ones, and I always return to Anki. Despite the fact that most other tools in my stack that I swear by are terminal-based.

His list is a list of reasons why he was motivated to do something. It does not matter how subjective the list is, since its purpose is not to convince others. It just matters that it connects with him.

If you're potentially interested in his project, you should evaluate your interest based on how much you think like him. If his complaints aren't yours, no skin off your back. Just ignore him. If they are, read farther.

Using Anki every day for about half an hour (I'm a slow learner lol). Anki sucks, but it's good enough that there's no point looking for other apps.