Looking at the amount of RAM phones have nowadays I don't know if this is an issue, desktop Linux runs fine with those amounts. Also Android is not really memory efficient so they needed this workaround.
You haven't tried to run a Linux on Mobile distro on your phone and compared the battery life to Android, have you?
Spoiler: I have :-)
I currently have 35 apps "open" on my iPhone, most of which are probably React Native or similar.
Other times I'm sure I've hit 60-70.
Because of iOS's app management feature, most of the apps are actually dead, but if I go back and open any of them, they will open and load on the screen on which I left them.
Android does this too.
Desktop Linux cannot.
Can I open 60-70 or even 35 Electron apps simultaneously on 8GB of RAM on Linux?
And no, I do not want to to back to closing apps, that is simply an inferior experience.