I mean, melee DD wise they are all different and have a special playstile. Be a Nin is a choice and you choose it because you like the class not for TA. Same for other players that like Monk because of form, stance and position or other that like to jump so they Drg. They are all good and valuable and all increase party dps. If you don’t like any of that, can just play Sam that is fun, flashy and much more straightforward. Sam has no party buff but deal 1-2k more than Nin so they both Equally provide benefits to the raid group, high dps = quicker kill. I personally don’t play melee at high end level, tbh I don’t like positional skills xD
Most of XIV players are happy with burst rooms, I am levelling up a DNC and can’t wait to learn my Flourish 60 sec skill that proc everything at once, Amazing I am ecstatic!! Plus as a Dnc you can stack up fethers for your ogcd skill up to 4 and use them when you want (in burst windows
). Imagine 4 weaposkills proc + 1 FD3 proc+ potentially up to 4 FD1 ocds already prepared and potentially other 2-3 FD3 proc all to sink in a 10sec room, that’s like DDs Heaven ^^

Btw about the tanks 10sec burst windows, I was crunching some numbers rq:
DRK:5BS+ 2EoS+C&S+Plunge+AD = 4850 dps * 10%DA buff ——> 5335
If you add an extra EoS its a bit more

WAR: 1IC + 4FC+ Ons+ Upheaval = 4190 dps + SE 10% buff ——-> 4191 all will crit tho

GNB: SB+ BZ+ BS + GF(continuation) + SC(continuation) + WT(continuation) = 4740 dps + 10sec of No mercy buff 20% ———> 5688 ( you also have another combo and 2 skills can fit in No mercy)

As you see the GNB has nothing less than the other tanks damage wise! War wins only because of crit!