Yes, and no. If there's a good chance that nobody needs to be downgraded, then it seems to be needlessly causing a lot of upset customers. But, at least by doing this in advance, it opens more recovery options. It happened to me last year, where I got a text the night before the flight that my J seat was moved to the back of the bus. I called in, and got a J seat on a flight leaving 2 hours earlier. Had they waited until flight time to do the downgrade, I would have missed the opportunity to take the earlier flight.

It would be nice if I didn't have to call in to do the fix, and instead in such a situation if I could manage my own move to a different flight online, it would cause me less stress and wasted time, cause less stress on the AC call centre, and help them to solve an operational problem.