Huh, these are interesting things to note. Especially with the "harder to learn" aspect, since there was a lot of hand holding in the Red Box (heck, the game pretty much makes your character for you), and I recalled having little difficulty creating my own Level 1 Character using the PHB. Though it could just be me.
As for the PSF thread... I'll have to read that some day.
I haven't been able to look at the 4e Red Box, and I didn't get to use the Beginner Box to learn PF, so I'm going on reading the 4e PHB, and the PF CRB, so from that alone, PF is easier in my opinion to learn. However, the PFBB does also hold your hand through the character making process, as well as a solo adventure with that character, and then a group play, for those who want to be a DM (and it walks you through that as well.)
So, while I haven't had any experience with 4e Red Box, and learned both systems from there respective Rule Books, I have to say that PF is a lot simpler to learn, and with the shear number of expanding books (which you can, for the most part read for free, as mentioned) to read over and learn how to operate a lot of other classes, spells, feats, and other things. (Of course, this isn't to say that 4e doesn't have a lot of expanding material, because it does... I know, I've seen it. Not read it, but seen it.)
For players, yes - creating your first 1st level PHB 4e PC is harder than creating your first 1st level Pathfinder Core Rulebook PC. OTOH when I play Pathfinder Core I'm spending a good chunk of each play session leafing through the rulebook, eg trying to work out what my spells do, whereas with 4e I can leave the book at home.
And as for remembering spells, and feats, that is just something that comes with time, and experience. I know PF spells and feats, because I play PF. You know 4e spells, because you play 4e. After awhile, you know the stuff, and you don't need the book as much as you use to, if at all. (Though, we still keep the book near our table, just to be on the safe side of things.)