> I can ship a cross-platform application
And you can also un-ship it whenever you want, leaving users with unusable devices they paid money for.
That was always the case. Lots of “flasher” applications have had web dependencies where they’d download the latest firmware to a temp directory before flashing.
You can ship an offline, standalone HTML file you can open in your browser too (this might not happen often but my point is it's not inherent to the technology)