PAE isn't really 32 bit addressing, though. It's 36 bit addressing or whatever in reality, with just simulated 32 locally.
Indeed, the physical addressing becomes 36 bit, the virtual addressing remains 32 bit, so applications do not notice any difference.
In response to that, you've just said "Aha! but if you use this larger bit size addressing system, it works better!"
Your argument was "Well, I use more than 3gb RAM, so of course I have to use 64bit". All I've said is that with x86 OS you can use up to 64gb RAM. Well, you should be able to, but Microsoft sucks. Also, PAE doesn't make your OS x87 or whatever, it's still x86.
You're merely talking about a different number also larger than 32. Okay.
Again, notice the difference between physical and virtual addressing. PAE changes one of them. 64bit changes both. This has many consequences, you'd be surprised, not all positive (namely, noticeably bigger RAM usage by each individual app). So using x64 with 2gb ram or less is not a great idea at all, you'd shoot yourself in the leg, basically. On Linux I have other things to consider, as, unlike windows, each app has to have separate binaries for each architecture (x86 won't work on x64 by default). Steam app, for instance, is still x86-only, for any OS, as is Skype. Windows 64-bit has a built-in compatibility for x86 apps (even though they can't use the benefits of x64). For Linux, this compatibility mode needs to be set up (so-called multiarch), which is viewed by many linux users as messy (why do I need to have two sets of system file for x64 and x86, basically). It's not that Windows is any better, it just has two sets of files from the start.
Etc, etc. The question of choice is less straightforward than you think.
By no means I'm preaching that everyone should use x86. I use x64 myself on my main machine (from which I'm typing right now). I'm just getting a bit pissed off by this "Woo of course 64-bit makes your computer run so much better, are you dumb or what?!" nonsense.