This is largely a perceptual thing, and it can be difficult to wrap your head around, but it doesn't really matter. At all. The expected value is still going to be the same under target dummy conditions, regardless of whether you are playing a burst dps job or a sustain dps job. You can go a step further and say 'Oh, I happened to Crit 522 out of 590 auto-attacks that last run out of pure dumb luck but then we wiped, game is so unfair'. But again, who cares? Anyone can get a really lucky run. What matters is your consistency, pull after pull. This is especially true if you're a tank.

The reason why WAR's 'Crit RNG' received so much attention in Stormblood was because:
1) Increased focus on Crit/DH with the introduction of DH
2) Xeno campaigned for the current 'Critless' WAR design because it was adding RNG to the fflogs rankings

For good or for ill, this was the bandwagon that the community jumped on. WAR Crit/DH on everything, and so, they Crit/DH on nothing. So enjoy, players got exactly what they asked for.

Personally, I don't care too much about whether Crit or DH actually exist. I do think that this game doubles down on comfy predictability too much, and I'd really like to see more twitch reaction-based mechanics and job design which makes you respond on the fly. But that's just my bias. You might think that your spreadsheets are the pinnacle of mechanical skill, who knows.