Honestly I don't think that at all. The acquisition of Fox is what's made them change everything. Now they have to balance a ton more properties without them eating into each others ticket sales. This is a mistake they made with Solo. It's ticket sales where cannibalized by other huge movies around it. Had they stuck to their winter releases and had some better marketing I suspect Solo wouldn't have preformed as badly. Really that's speculation though.
Either way, what seems to be happening with Disney now is with the purchase of Fox they've had to shift dates around and re-balance the release schedule to make everything fit, it didn't matter before, because Fox was the competition, now it's in house and they don't want to be competing with themselves. Just how it comes off to me.