Make Instruments of Zeal Useable?

This is the only ascendency in the game that requires you to attack once every second instead of every 4 seconds or "recently"

nobody cares about only 82 people out of 125k using an ascendency?

You're talking about POE1 in the year 2025, soon to be 2026. These days telling someone to press an offensive button to clear the screen is considered to be too much work. Heaven forbid they have to press multiple buttons per screen clear. Hence the rise of "autobombers" and similar.

The inquisitor ascendancy is a funnel for absurdly expensive COC builds that often die to everything (even with block cap and high ES). Make sure to you have your mirror tier simplex amulet, perfect cluster jewels, perfect ES pieces, etc.

Self-casting in most serious endgame situations is not viable. Telling someone to attack before they can self-cast is just not going to fly in 2025.

It's just another case of "do the devs even play their game these days?" and the answer is "maybe, probably not to bother addressing or noticing this thing."