Only read the first post. Excellent exercise in building strawmen, but the intent of the devs seems clearly aimed at some skills which see extremely limited and niche use that it's hardly worth justifying having them on a hotbar. Especially because the amount of buttons you can reasonably and comfortably reach is finite.
Tempered Will, for example, is useful in an extremely limited number of fights, and where it is useful it's used as a crutch to prevent dealing with mechanics rather than feeling like an extension of your kit; a PLD can use Tempered Will to negate Sophia EX's tilt mechanic, but it's a lazy escape from doing mechanics and hasn't a lot of use outside that in contemporary content. I tried using it in Gooball Library and was pushed back by the book attack from the first boss, for example; maybe I used it too late but even there circumventing the pushback hardly seems worth having a (pretty long) cooldown skill for.
Monks have Haymaker, which virtually never comes up in any content with a tank (hint: 90% of content), and Dragoons have Feint─the use of which is a loss of DPS in most cases and, off the top of my head, only slightly useful against Garuda Extreme provided you hit a very narrow window of opportunity for a marginal benefit.
These three are skills that have little to no real effect on your raiding experience or even dungeon-conquering experience. Re-assessing these skills may result in them being combined with other skills, or adjusted through traits gained after level 60 to transform them into more useful skills. I think the idea of "re-assess" isn't to outright delete them and pretend they don't exist, but to provide additional support to make these skills useful in more content than they currently are.
EDIT:
Just to point out, but at level 50, a Dunesfolk Lalafell Black Mage could use Thunder 2 instead of Thunder 1 during their Umbral Ice moment. Thunder 2 definitely saw some more use back then, and even now I sometimes manage to squeeze in a Thunder 2 instead of Thunder 1 without losing any uptime.Honestly, BLM sucks for combat space in general anyway, if they combined thunder 1 and 2, or thunder 2 and 3 together I could fit Transpose onto my front bar. So I'm all for them removing something from them.