While I mostly agree with him, it’s hard to know “what’s going on.” Is it just the uncompromising gram-counting that pervades the bike industry which leads many high-end mountain bike brakes to be inconsistent, spongey, unreliable or otherwise lackluster? I think another problem specific to MTB brakes could be the high mechanical advantage required between the lever and the pads to get enough power with one-finger braking; any air in the system, flex or seal squeeze is multiplied at the lever by the overall leverage ratio, leading to more sponginess and bite point inconsistency.
A high leverage ratio between the lever and pads multiplies power, but may also magnify any inconsistency or sponginess.
Whatever the cause, it does seem to me that a ridiculously high percentage of brand-new, high-end bikes come to us with less than ideal brakes, and even after a thorough bleed, the inconsistency in lever feel that we’ve been complaining about for years can remain or come back after a few rides.
But are we making a mountain out of a molehill? Are you happy with the performance of your brakes?