Each electron App is actually a full independent chromium browser install running a website. It’s easy to code for and works cross platform as a result, but it’s essentially just a website, although they can run offline depending on what’s been built in to the local app.

Each electron app running on your system is a separate full chromium app running, with no sharing of resources between each instance. So they take up a lot of space each and duplicate all the resource usage, and potentially the security flaws.