While I'm not one to say Reapers are the be all end all, I really like them personally, my main issue is with the reply.
This is remarkably flippant *and* inaccurate. I assume these shots are from the fabled markerlighted Riptides the internet is so obsessed with, given 3 shots are killing that many models. Lets ignore that 1/6 of them fail to fire at all due to overheating and some will miss due to scatter.
One of two things has more than likely happened before this:
The Eldar player went first and thus has the opportunity to put a full volley of fire into those cover ignoring markerlights and certainly wiped off the ones in range of his unit and quite likely then some, realistically killing a Riptide or 2 as well before
NOVA reactors can be fired up.
The Tau player went first in which case why did the Eldar deploy his unit in markerlight range given it is less than the Reapers own fire range after movement which they can do effectively and pathfinders cannot?
Now Tau can get more mobile markerlights but once again either the Eldar can deploy to minimize their effect on the unit or gets to shoot them first barring getting seized on, then there's
LOS blocking terrain... it's a complicated issue. Plus of course not everyone in the world plays triple Riptide Tau, despite what the internet may say.
As for the unit itself, it's a nice combo that will certainly put out some serious damage however it's more vulnerable than classic hammer units with the same price tag that will make it struggle at a really cut throat level. Investing that many points in a unit is usually done because the unit is durable enough that even if your opponent goes after it they will stand up. The Farsight bomb, Screamerstar or Jet Council are handy examples of this.
Even with the Crisis Commander tanking the wounds the unit really isn't *that* tough, not as weak as Formosa makes out but if your opponent wants it bad enough they will go down and your 5-600pt linchpin is gone.
Edit: Spelling