The average end-user has less than 4GB of RAM and would struggle to run electron apps at all. They would get frustrated with the computer being slow but would not know who to blame.
Aside from that, electron apps do not look, act or feel native.
It really depends, some work might necessitate 8GB+ but most really shouldn't and only do because the tools they use were built by developers with that much RAM.
At work I need my 16GB but that's because Visual Studio and the app I'm working on the most are memory pigs. Visual Studio 2017 doesn't really have any compelling features over 2005, but 2005 ran quite comfortably in 2GB, so with this piece of software alone I need a lot more memory for no gain.
At home in the other hand I have a fairly low end (and now 3 year old) dell laptop with 8GB of RAM, but with my current c project and DE (i3, riced way more than necessary) I'm using less than 2GB (with vim+unix as the IDE), so plenty to burn when required. This is a more productive environment too, I have a fully incremental build that will compile, run unit tests and run memory tests in the blink of an eye every time I save a file, so I'm getting much more feedback much quicker than I do with Visual Studio.
Devs on lower resource machines will also be dogfooding much better. If their apps are slow and bloated then they'll feel the pain their users will and be much more likely to address them. Windows 10 might have a start menu that didn't take several seconds to open if the developers weren't on top of the line surface pro's.
I can work productively on my 6yo notebook with 4 GB RAM, because a terminal, CLI tools, vim and a browser covers my needs. If I had to use Electron apps, I'd probably have to look into buying a new notebook, which is quite wasteful both on the money side and on the material resources side of things.
Some developers will probably need more than that because of the resource demands of their specific fields, but other than that, 640 KB ^W^W 4 GB should be enough for everyone.
Aside from that, electron apps do not look, act or feel native.