The real question is how we got any portable solution to this problem in the first place.

To me problems are fundamentally economic and political, not technical. For example, the unique circumstances that led to a portable web standard involved multiple major interventions against Microsoft by antitrust regulators (in 2001, 2006, 2009, 2013, etc). The other tech giants were happy to go along with this as a way to break microsoft's monopoly. Very soon after, Google and Apple put the walls straight back up with mobile apps.

If you go back before HTML, OS research was progressing swiftly towards portable, high-level networked GUI technology via stuff like smalltalk. Unfortunately all of the money was mysteriously pulled from those research groups after Apple and Microsoft stole all the smalltalk research and turned it into a crude walled garden of GUI apps, then started printing money faster than the US Mint.

Whenever you see progress towards portable solutions, such as Xamarin and open source C#, React Native, or even Flutter, it is usually being funded by a company that lost a platform war and is now scrambling to build some awkward metaplatform on top of everyone else's stuff. It never really works.

One exception is webassembly, which was basically forced into existence against everyone's will by some ingenious troublemakers at Mozilla. That's a whole other story though!