> Sounds like more than half the problem is the lack of standardization in desktop operating systems. There’s no reason why all Mac apps can’t take advantage of the system standard tabbing like AppKit Mac apps do, but most don’t, so in most apps you don’t get apps unless the dev implements them.

Yep. "Every app ships most of Chrome" is a profoundly stupid way to get a sensible cross-platform application runtime to develop on, but it's the only one that works, and at that point you might as well make the app run in actual Chrome instead.

> general flakiness stemming from nobody being able to agree on how to develop web app UIs (even just within the React sphere, let alone beyond it). The number of manhours set on fire and level of potential for refinement left on the table by the innumerable redundant bespoke widget reimplementations is unreal.

Disagree. That's creative destruction at work, it's messy but it's the only way to get better. Like it or not (and I don't like it), the best UIs around these days are built on React or similar webtech.