There are some differences, because the advantages to the "advance planner" under FP+ are not as stark as the advantages offered to the wily FP runner of old. Advance planners still can't prebook more than 3/day, they still can't prebook two experiences on a single attraction, and they are still subject to the tiering rules in Epcot and Studios. So, at least in those senses, FP+ is more equitable.
Furthermore, I don't think "no advance planning" at 5 days is quite accurate---to get anywhere near the maximum benefit from old-style FP running, you had to do a good bit of study at some point. Veterans could amortize that over many visits because the rules changed infrequently, but a newbie with no advance planning as of 5 days of their visit was at a disadvantage in either system.
On the other hand, if you are willing to do *something* as late as 5 days out, FP+ is still useful. As I type this, the EasyWDW "least recommended park" five days hence is Magic Kingdom. I can book FP+ for a party of two for any operating FP+ attraction in MK except MSEP, A&E, 7DMT, and Wishes. That's not terrible.
That said, I do agree with you that FP+ is designed to favor advance planners. Indeed, I suspect the decision to favor advance planners is another very conscious one on Disney's part. Over a decade ago, Disney leadership gave
a presentation to a bunch of stock analysts. Here's one of the things they said:
Mind you, this was BEFORE Magic Your Way, the Dining Plan, Magical Express, etc. were deployed, let alone FP+, Photopass/Memory Maker, etc. If you think about it, nearly
every innovation Disney has come up with in the past decade has been to encourage guests to plan things in advance, and to lock as much of that planned time to Disney as possible.
So, yes, the system favors (i.e. encourages) advance planning, because those who plan in advance are
more profitable.
Yep. And Disney's bet---and it's an all-in, multi-billion dollar bet---is that the number of angry/sad people will be vastly outweighed by the increase in satisfaction that the casual guest gets from prebooking, and the increase in vacation time/dollars captured by encouraging more and more people to plan a little something in advance. It's hard to say that would be true only reading the DISboards, but the DIS is not at all representative of the average WDW guest.