How is that abuse? He secured an Ice planet right next to the enemy homeworld and said enemy gave him tons of time to build up population. People are not used yet to the fact this kind of slacking will end up in your fleet getting busted, so it should be fine. (Also note the Ice planet was not yet at full population, if I recall correctly it was "only" at 100 pop)
So what, he's supposed to give up his favorable position to attack head on a planet with a titan, starbase and superior fleet, rather than force the enemy to attack him where he's strongest? Also if he did attack, couldn't Quar just use wail of the sacrifice from the terran behind the ice for even more damage?
From my understanding breaking up stalemates or enabling you to do a comeback is exactly what the ability should be doing.
I thought it was intended to be a last resort defensive weapon, where you sacrifice the planet to kill an invading fleet, not use it to pin your oppoenent in an unwinnable situation.
Last but not least: It does damage to you. It kills your population and planet HP on one of your planets. If you screw up on the timing you could end up with an enemy taking over that world in its wounded state (i.e. if he used an Akkan to protect his fleet for whatever reason, or if you used the ability too late when trying to decimate a fleet jumping in on your world).
Indeed, its high cost is what I thought would prevent it from being widely used. But in that situation that ice world was absolutely useless to Quar, his economy was good and unthreatened, and most of his income was probably from trade ports, so tax income doesn't mean much anyways. If wail also damaged his units, at least he'd have to with draw his fleet a ways first so they'd have time to prepare or possibly strike first to prevent the activation.
Also about the Akkan, another reason wail is so much better than say missile barrage or the red button is at least you have a warning that its coming. The only way you'd realize its been used is if it kills a capitalship. Both terran and sanches didn't even realize it until after the invasion fleet arrived. There would need to be some sort of video or audio warning that it was about to be used for armistice do do anything.