The dependency on Chrome is a turnoff for people who don't already use Chrome. An Electron app just depends on the operating system (apparently), so the install is much like other desktop apps.
PWA's are a sandboxed environment, where devs do not have control of browser version, cannot modify chromium, and cannot bundle necessary binary code. Even Spotify bundles in faster JSON parsers, and probably a number of other things.
An average user might not be able to connect the dots this way and realize what's going on with their machine. They'll just complain "my laptop is slow all the time and I don't know why". As developers, I feel like we have a responsibility to take better care of our users in this manner. Using a solution that will consume a GB or more of unshareable memory for something that doesn't need it (which is mostly everything) is a poor choice that puts the developer's needs (write-once-run-anywhere; faster, cheaper development time; fewer developers needed) over the user's.
So I fundamentally disagree that users only care that the app does the things they want, and nothing more.
Is this part of what Microsoft is doing with Chrome being pre-installed (via Edge)? I can't find a source, but I heard that using the existing chrome on the machine would reduce disk size for applications and possibly even allow them to share memory.
What's the reason, lack of discoverability? I'd rather run one Chrome instance than a dozen apps that use varying versions of Electron.