[hakfoo]

Is 1) such a bad thing?

There aren't really that many apps that make sense to work in a full-fat form all the way from wearable to phone to tablet/laptop/desktop.

Tablet/Laptop/Desktop is probably solvable by a single toolkit set (remember the brief era of Windows 7/8 tablets, many of which had fold-back or snap-on keyboards and pointing devices if you needed precision beyond what a touchscreen could offer?) but I don't really want to run KiCAD on my phone or a smartwatch, for example.

Saying outright "we have different tooling for big and small devices" (or even three sets-- large device/handheld/wearable) should steer developers into providing tools built to the task and purpose. Maybe the phone/wearable version only has limited tools that work well on a tiny screen and is as a result smaller and more efficient?