I know speed to market is important, but it's always a huge turn off to see new desktop apps be non multi-platform. It makes me question if other OS platforms are really a priority, even if they get added later.

They use webkit, so macos/ios was the natural place to start, but they have started working on a linux version. If they had gone to make another chromium fork they could have probably have it multiplatform by now, but I am glad they did not.

The article says they are currently working on Linux and Windows builds

Why do you want to use the same browser on all platforms. Diversity is a strength.