Mantra is such a weird utility tool...

[Neela]

When are we questioning it then?

Ex primals are mechanic dependant on its uses (which is fine, not all skills need to be used in all fights, as a PLD I can definately attest to that), Nidhoggs Ahk Morn is a good time to use it though; and as for dungeons, i've been beginning to notice that physik on my SCH is an unnecessary skill, let alone mantra

Well regarding to OPs question it doesn't seem that he have been in raiding yet ^^

(...)
What exactly is the point of mantra? It's range, CD, and duration is all so limited you can barely plan around it unless you use it as a prepull buff or before a bosses ultimate.

It feels like a rather forgotten tool to me.

I do too!
But the way this game plays, it comes off as useless. Of course, when raids deal a lot more damage it'll be better, but right now it's just "more damage more damage!".