Actually if you watch the video he clearly Blames Blizzard for opening the door to people feeling obligated to do the grind to be competitive, because, at the end of the day, if it can be done, someone will do it. And if you don't do it, you will lose out to someone else who does.
That's the problem they are addressing by bringing back exponential scaling. And there is no reason it won't work. Actually when the scaling was fully exponential, it did work. As Blizzard freely admits, the problem came in when we hit that last trait, and everyone was capped at AK25, and then the cost scaling went linear, and there was "no excuse" for not maxing out any more.
When AP cost of traits scales up exponentially, and AK benefit scales along with it, then the AK work order cooldown puts an absolutely effective soft cap on the level of progression that even the most fanatical grinder can attain at any point in time. So long as those scales remain in lock step, and the AK levels keep coming so long as we have more exponentially expensive traits to buy, it continues to work right on through to the end.
You can go nuts if you want, but you will never get much from it. And the person who does nothing for a week and comes back when the scaling has caught up again, will be right on par with you in a fraction of the time. Spend a ton of time right now, today for a tiny advantage that won't last, or wait a week and get the same advantage in a fraction of the time. Your choice.
In the meantime, the people who go all out playing 24x7 are never going to get far enough ahead of you to make a difference. Yeah, you can spend twice as much time as the next guy for 1.5% more performance. And then the next guy outplays you by 2% and wins anyway because he got some sleep and isn't burned out.
The reason that AK actually works is that it is a global, across the board, forced march pace that puts an absolute cap on how far progression can go, for anyone, at each point as the expansion goes on. You can call it a soft cap, but bang your head against it for a while and see how soft you still think it is. And there is no way around it. You can roll five alts if you want, but they will all hit the same cap. You can grind AP all you want, but those traits won't come any quicker.
Unless you figure out some way to time travel to a month from now when AK is 10,000 percent higher, you are never going to get significantly ahead of anyone else for any meaningful length of time. (And even if you did figure out how to skip a month, you would find that everyone has caught up with you in the meantime.)
Of course there are still other avenues for gaming competitive progression like split raiding and such that aren't touched by fixing artifacts. But with the dominance of the artifact over your stat budget, and the limited options for working other sorts of gearing advantages, at least artifacts will not be making the situation worse by adding a whole other problem that is an order of magnitude worse than anything else we already had to deal with.
The fixes may be too little, and too late for guilds that already are burned out and decided to call it quits rather than signing on for more of what they had to deal with in the first six months of the expansion. And it's not an approach that everyone is going to love. But it probably is one that everyone can live with.