Electron apps can be packaged up as UWP and submitted to the Windows Store (with the restriction that you can't currently target Xbox, HoloLens, or Windows Mobile via Electron)[0]
To the contrary, I think they're encouraging Electron apps. Electron apps can be packaged directly to Windows Store. Another case in point: Visual Studio Code.
[0] https://www.onmsft.com/news/electron-apps-can-now-converted-...