Of course it is. That's been obvious from the beginning---FP+ is essentially a redistribution mechanism from those-in-the-know to those-less-in-the-know. Those who understood the system, and who realized the benefit of being in the park early in terms of getting more and better access to FP, had much better access to attractions without wait times than those who did not. FP+ places a limit on those-in-the-know: three total, no more than one at any single attraction, and in some parks a further limit on the most in-demand attractions/experiences via tiering. Those opportunities will go to someone else instead.
From Disney's perspective, this might turn out to be a great thing. Yes, they might lose a few hard-core FP maximizers who find their trips unacceptably altered. But, if they can make up for that with a larger number of happier guests---happier to return, happier to spend while they are there, happier to recommend WDW as a vacation destination to others---then on balance Disney comes out ahead. Or, it might turn out to be a disaster.
It's also fair to say that those of us who are FP maximizers are also the folks who find the best deals when we are there. Losing us in favor of folks who don't squeeze every last penny out of a trip might also be a good thing for Disney.
One thing we can't dispute: it's a different world. It's not going to work as well for some of us as it did before. Time will tell if Disney comes out ahead, but it's a big bet for sure. I lean in the Disney-knows-what-they-are-doing camp, and suspect this will work out better for the bottom line in the end, but we'll just have to see.
I haven't been to WDW since FP+ started testing; we went to
Disneyland last winter, and Disneyland Paris over the summer instead. Our next WDW trip is this upcoming April. It will be an onsite trip. I'm expecting to have access only to FP+, and not legacy FP. To be honest, I'm looking forward to some aspects of this, even though we'll be riding the headliners less than we "used to." I am not going to miss trying to figure out when to go pull a fastpass for <insert-ride-here> and how to manage criss-crossing the park to do so, for example.
As an aside, I think that in some ways enforcing return times was an even bigger deal than limiting FP+ reservations. With enforced return times---something I've experienced now in Orlando, Anaheim, *and* Paris---I no longer return each night with a pocket full of unused fastpasses that I pulled "just in case." I'm also already doing the headliners less often, but I'm using that time for other "lesser" things, and finding that those things are surprisingly fun, too.
If FP+ goes the same way, we might all find that even though our trips are different, they are no less fun.