I would only disagree with your last sentence. In that after 40 years of watching computer tech develop, stating "always" in this way, seems to me to be just like saying "never" as in "There will never be a time when dedicated hardware will be unnecessary." IMO the history of computer development is the embodiment of the idea... "Never Say Never".For mixing / mastering, absolutely. But dedicated DSP chips are always going to be better for real-time actions like low-latency recording. Computers are (by design) multi-purpose machines, and there's no way to ensure that something else isn't ramping up the demand on processes just when you need your CPU to be processing a convolution reverb. It's hard enough for the computer architecture to keep the disk i/o running smooth enough to allow multiple tracks to be written, let alone trying to also maximize available processor power.
Dedicated hardware will always have a purpose, even for prosumer uses (IMO)
I'm not disagreeing with your assessment of the current state of low-latency recording - I kinda said so in the previous post. But to assume that situation won't change - through changes in prioritizations within OS's, simply having so much, faster power rendering it a non-issue, or other solutions not yet conceived - is a prediction I put zero faith in.