Yeah many people do not just have the time to look into this, and most companies don't really care, as we have so much RAM and CPU power these days, so I can see why for example many messaging apps just choose to write their app in Electron, instead of trying to figure out how to do it natively cross-platform, which can be a more PITA especially when you also have web as a platform.
This feels like... a trap.
I think there's a complexity in doing that which could be summarized as follows: it's possible, but the more complex your codebase, the more difficult it is to reason about how to get to or maintain that 80%.
Even if we assume that 80% is the maximum, if most products (or the notable ones that we all complain about, I suppose) are hitting 50%, then... well, that's a problem.
For full disclosure: I've defended Electron on the merits of "there is sadly no better way to ship cross-platform UI-based software". I criticize it with this in mind.
You can make an Electron app not slow/a battery hog, but it requires working backwards from a state of "what on earth is going on under the hood here". This is the inverse of building a native application, where that complexity is often introduced by you. I personally find this significant - you can teach someone how to avoid the latter, but it can require crazy amounts of insight to learn to debug the former.
It is 100% possible to build better Electron apps. I trust almost nobody to actually commit to doing it.
Also, particular yet tangential to this thread: apps like Signal or Discord which still make their Electron apps run under Rosetta 2 on an M1 are a nuisance. I just run Discord in a browser tab at this point.