Super-light, small form factor device with mouse support = MacBook.
Super-light, small form factor device with touch = iPad.
Have any of the "iOS needs mouse support" people actually thought about how it would work? iOS doesn't even have a pointer anywhere in the UI, or scroll bars, or dropdown lists with a picker that would work with a pointer instead of touch. The whole UI is engineered exclusively for touch. Surface works with both touch and mouse because it runs normal Windows with touch support added. iOS is not macOS with touch added (thank God). Mouse support in iOS is not going to happen, apart from some niches like per-app support for mice in RDP clients.
Finally, before anyone brings up the stylus/pencil thing again because Jobs said in 2007 "if you see a stylus, they blew it":
- He was referring to the resistive touchscreen devices of the time where you needed a stylus for touch accuracy in comparison to the then-new capacitive screen on the iPhone - he might as well have said "if you see a stylus that you have to use to operate the UI, they blew it".
- He was referring to a device with a 4-inch screen, not a 9.7"-plus one where there are much greater opportunities for drawing etc.
- The Pencil contains a lot of tech (pressure / angle sensitivity for a start) that the dumb styluses of the day didn't have.
Mice in iOS is not the same thing.