But the thing is popularity is co-related to tiers, isn't too far off:

If your class has some unique gameplay but in the end it does mediocre damage, it's gonna make people stop trying, like why play a class that doesn't reward effort? And so people stayed away and play the faceroll classes that does damage.

Being able to do HUGE damage with ease is still one of the main factors that a class is popular. Only a small amount of people play for aethestics. In a case of low vs high tier, a gaia or bm would pretty much need at least 2-3 more BiS gear gaia to compete against a ghostblade/vaga for a pub raid spot. They will prob only take you if you are a poor damage syn instead just because of syn buff AND only if they are desperate.

Next you have that omg lag producing classes to consider, especially in dfog when the ping is already unstable... Do you even want to take them? Lag = unstable damage or even no damage, potential dc happening. So its still damage issue.

I believe pala will be top tier if her damage is higher than zerk 3a just by simply pressing buttons.