Nope.
His example is totally spot on in terms of how much fire is fucked over by crit being 50% less effective.
Fires relies on crit chance fundamentally yes...........but crit hit damage has a huge effect on not just burst but sustainable damage which comes from ignite and pyro dots.
Ignite damage is calculated on you damage done by a single spell, like pyroblast, then multiplied by you mastery value, because of the coefficients being tuned for PVE (200% crit damage), and fires damage being based around chain crits to build big ignites when you apply the same coefficients to the PVP values, your damage literally plummets as it makes stacking a decent ignite very difficult.
Your burst cooldown, combustion, is a calculation of how large your ignite is so is also directly affected by how much crit damage you do.
If you played fire mage you would understand this.........