Honestly depends on how many important regular buttons you have to press.
I found the sweet spot to be around 18 Buttons to press regularily within a rotation or otherwise active enough regular skills and about 8 skills that have a more niche uptime or otherwise long CD.
Wouldn't mind more if they are buttons like stances or extremely situational (repose, undraw) but even if the total buttons is above 26, I'd be fine as long as the active buttons won't be above 18 as I'd have to click any other buttons above that number.

This was especially apparent for me while leveling Samurai and Blackmage.
Jobs that had it just right were Dragoon and Summoner for example.

I'd only assume that they are aiming to stay below 32 though to not mess up with comfy controller play but even that would mean hot bar swapping if you wanna slot in important markers and 2-3 important general slots like teleport/greeting macros.