Not sure about the 2 specific apps posted, but web applications packaged as electron apps often do so in order to easily escape the normal browser sandbox without having to prompt for permissions? Or even call into native code which would be impossible from a web app.

I would not think that because an app is electron based, it is sandboxed from your system.

Ideally if you can run the same app under your normal web browser, you'd be fine. I see many people install the Slack app for example, but the web version works just as well within the full browser sandbox.