Although the majority of home computers now-a-days have 64 bit processor, 32 bit operating systems still hold a place in this world. Amongst the majority of the older machines that are still running that are IMMENSELY vital to sustaining the world's cogs but are old enough to be 32 and hell, sometimes even 16 bit with the case of the United States' armed branches as an example, there are also still times where 32 bit operating systems are just the better solution. 64 bit operating systems tend to be bulkier, and while that works on a home setup of 6+ GBs of RAM, that might not work out for a simple, 2 GB machine that has a slow processor and slower hard drive.
On top of that, there's also nothing or a very limited variety of commodities akin to WoW64, a Windows on Windows "VM" of sorts(it's not really a VM) that supports 32 bit software on their 64 bit operating systems, akin to WoW32(if that even exists, I know their 32 bit operating system STILL support 16 bit programs and I assume it's through a similar method to how their 64 bit operating systems support 32 bit programs.) The thing is, Linux and MANY other operating systems simply do not have this luxury, and thus are restricted to their respective programs. This means that if you got rid of the 32 bit Linux builds or what have you, you get rid of all that 32 bit software that might be decades old without any sort of replacement.
Finally, the VM argument. This is idiotic on so many levels, but I'm not as into Linux as I am Windows, so I can't say very much on a technical standpoint, other than the hardware might be too slow to support this, and according to a friend who knows more about Linux than me, the audio is extremely tricky to work with. This all makes Linux gaming basically impossible because of the amount of 32 bit games, as well as a few other things with CPU intensive programs that might run fine on bare bones hardware but not so much in a VM.
In conclusion:Throwing away 32 bit OSes entirely is a bad idea. Even if you had a WoW64-like option on your respective operating system, allowing you to run the software you definitely throw in the trash normally(see Windows XP Itanium-64, which doesn't have WoW64 and is a horrible nightmare to get through) upon moving to a 64 bit OS, the hardware might not be up to speed to handle it.
Edit 1:For some ungodly 2:56 AM mind bending reason, I called WoW64 WoW32, and thus have corrected it.
