IF small form computing paradigm shifts, I'll be back. IF bots negate the app gap, I'll be back. IF UWP jump-starts W10M apps, I'll be back. IF the iOS bridge produces tangible results, I'll be back. Multiplatform development can be made 'easy', but it still takes some (always limited) resources and a business case. I get the impression that MS is even having a hard time getting developers to buy into doing the (minimal?) extra work to put UWP apps on mobile. Like I said, perception is part of it.
Market share is important to spur efforts from developers. Does a developer allocate resources to porting from iOS to W10M, or does a developer put those resources into constantly improving and competing in the iOS and Android markets that are now putting food on their tables? MS needed to make that decision easier and 10%+ market share would've helped. MJF recently stated that 80% of the MS contacts she talks to are on iOS or Android. Softies need to get stuff done too, and today and tomorrow people use apps to get stuff done. As far as the American banks go, when have they ever really given three chocolate cakes about their customers as people. They are only going to do what is necessary to compete against each other for business. They've tried WP apps and have crunched the numbers: not worth it. Now market share is declining and UWP or iOS bridge is supposed to make them eager to return?
I'll be rooting hard for W10M because I do see what could be and I do vastly prefer the OS over the alternatives. But I will be cheering from the sidelines for now. Just like MS, I'm making a business decision, not an emotional one - the business is me getting my day-to-day stuff done.