I guess there's the distinction between capacity that could be taken up by other things, and free capacity that doesn't necessarily cost anything.

For a server built in the cloud those cycles could actually be taken up by other things, freeing the system and bringing costs down.

For a client computer running electron, as long as the user doesn't have so many electro apps open that their computer slows down noticeably, that inefficency might not matter that much.

Another aspect is that the devices get cheaper and faster so today's slow electron app might run fine on a system that is a few years away, and that capacity was never going to be taken up by anything else on the end user's device.

It’s more likely that Electron app uses poor code and have supply chain issue (npm,…). Also loading a whole web engine in memory is not cheap. The space could have been used to cache files, but it’s not, which is inneficient especially when laptops’ uptime is generally higher.