Re: @Lee D
Nothing to do with that.
Did you know games are 64-bit only and demanding 16Gb+ RAM nowadays? That's not the top-end gamers only, but just to RUN the game on Steam.
As you can see from my post, I deploy 8Gb by default to ALL USERS, and I work in a prep school. That means primary-aged children, and staff who run nothing more demanding that Word, Outlook and Chrome. Because 4Gb vastly increases their performance (and coupled with an SSD for some staff makes ancient Lenovo desktop machines that they don't make any more FLY). I'm sitting on a ThinkCenter E72 in work, it's hardly a power-user machine.
As people have noted above, a browser can suck up Gigabytes (and, sure, some of that is page caching, but by far not all). The latest series of phones have 3Gb or more, what makes you think that they are doing more than people's desktops?
Yes, I have VMWare. But none of my client computers in work do (or HyperV, that's for servers). Chrome tabs? Gosh, why would any unexperienced user open 30 tabs at the time (something I could do back in the Opera 3.6 days without ANY HASSLE AT ALL on a machine with way less RAM)... because they're users who click everything and don't even realise they have other tabs open half the time. Windows 7, 8 and 10 all RUN with 4Gb. Fine? I wouldn't say that. That's WHY I upgraded... when I started at this workplace that's what they had (P.S. that was 5 years ago, and it was considered a "cheap" solution even then). User's complained that the machines were slow. So the upgradeable ones got 8Gb, the others got SSDs (note: All machine running 64-bit Windows, but some motherboards aren't built to cope with >4Gb RAM but some of these clients are models that are 10 years old, so hardly surprising). Both provide an ENORMOUS boost to the system.
It's about being sensible... the cost of 4Gb extra RAM is pitiful for the performance improvement. It also drastically reduces swapping, especially important if you are using an SSD. I have actually seen 4Gb machines with no swap just run out of memory (hint: I have Outlook and Vivaldi loaded, with Sophos and some TINY utilities in the background, on the WORST machine in my worklpace - always eat your own dogfood. It's left running all the time. Once a week, I get a "we've closed this program because we were running out of memory"... and that's on a machine with 4Gb and swapfile on SSD [which is slowly killing the drive but it's surviving nicely]).
I'm not just making this stuff up. Go buy a cheap laptop and put an extra 4Gb in it. The value is way above a more expensive laptop with only 4Gb.
Your disk must be swapping all day long with only 4Gb on a modern OS running even basic Office and Chrome for any significant working day.