Decoupling might have benefitted JavaFX, but it did not benefit me who develops professional desktop applications for a living, and it did not benefit my users.

If they wanted to decouple, they first should have created a cross-platform jpackager-like tool that generates native executables for major platforms.

I remember JavaFX was launched with great fanfare as a modern replacement, which it certainly might have been - a modern, efficient platform. I am afraid it will slowly decay and dissolve into oblivion to be replaced by gigabyte-size electron apps.