I get this perspective from the developer point of view, but I'm not a video editor. I'm a person who occasionally edits videos. Elsewhere in this thread I mentioned that I use vidcutter, a free and open source tool that does the same basic task. After installation it takes 14 MB on my Linux distribution (it's a 4 MB download).
The thing is, I have dozens or hundreds of tiny little utilities like this installed that make one-off tasks that I do once a month or so much easier. I can't afford for them to be Electron based on my 128 GB SSD. For people who edit videos every day it's obviously not an issue, but I wouldn't be surprised if the majority of people who use tools like this don't use them every day. Maybe not even every week. All this extra space adds up.
I think, in fairness, that a lot of the anti-Electron criticism comes from Linux users like myself. Windows users expect to have everything packaged as one gigantic binary with all the dependencies. (Vidcutter is a 175 MB download on Windows.) This strikes most of us as "poorly engineered", which for some is already enough of a reason not to use something. On Linux, the norm is that distribution maintainers put together a package with the dependencies separate, and these are shared between multiple packages. Electron applications are rarely distributed this way, and that's the biggest part of the problem and the source of a lot of the bloat from a Linux user's perspective.