Robbing gap closers of damage makes the game even less fun.

[Shurrikhan]

The problem with gap closers that provide a net dps gain is that damage takes priority over movement.

Not when the movement provides uptime that in turn provides higher damage.

When your relative potency-per-GCD is over 400 and using your gap-closer under damage every possible (raid)buff available to you is 50 potency higher than using it outside those raidbuffs, it still takes at most a third of a second for holding one of your 2+ charges for that movement requirement to be a net DPS increase.

Movement WAS gap-closers' primary means to net dps gain unless there were no potential loss of uptime to be had anyways. Which is a problem then with a lack of melee mechanics, replacing bosses increasingly with DDR striking dummy play, not with having some way not to waste the given button when it'd otherwise lack any use.

It's a bit of a shame that all the new gap closers introduced in Dawntrail seem to be Thunderclap analogues.

Why wouldn't they be, though, now that you've stripped them of damage? To-target damage-less skills are just objectively and needlessly limited if they only go to enemies. That effectively leaves En Avant-likes, Thunderclap-likes, or Shukuchi-likes, or being getting flavor only by being needlessly more limited than others. The flavor already existed prior, in

It still amuses me that the WAR playerbase successfully campaigned to replace their on-demand Onslaught with a standard 30 second recast gap closer that has to be used for damage.

You mean Nyx, Xeno, and all of ~4 others? A vocal handful does not a "playerbase" make. The rest were quick to point out that Onslaught being its 10s CD and spending gauge was integral to offensive minutia atop being a far more compelling and flexible tool than any "free" (read: tuned around use within raidbuffs) 30s CD would be.

Note: Onslaught also had to be used for damage before. It just did that through correcting gauge value and interaction with Internal Release, both more thematic, atop exploiting raid buffs.