This is one of the more annoying problems with our industry. People rediscover solutions from 60s and 70s and sell them as if they were new and revolutionary...
With the popularity of things like React, you now have a powerful way to express how the UI looks in every state, not just the initial one.
Step 1: People realise that Electron apps look different and do not fit the OS.
Step 2: Big company invests and creates a library that supports Win/OSX looks.
Step 3: Same big company creates a RAD type tooling for it.
We present you a revolution - Big Corp. RAD Tooling 2020 a la Borland Delphi 2007.
This is not an issue for most people. I like to use Spotify (the desktop app) as an example - it's a pretty good looking app, works nicely, and yet it uses an HTML-based UI.
Microsoft's own UWP also looks vastly different than native Win32-based apps.
The resource usage and slowness of Electron apps is a problem, but that is caused by using the entire browser runtime. When it comes to the capabilities of a UI framework, one of the questions I ask is "Could you build something like Spotify's UI with this? How difficult would it be?".
I guess the question boils down to whether a single tab in a browser which is properly managed by OS can compete with a good old native desktop app.
So far the facebook stack and react-desktop seems to be the best candidate for that description, but I don't neceserily think people would focus on getting it to the desktop styling. Universal Material UI (or similar?) probably would overtake that approach.
Modern? Are you serious?