Rule of the lowest common denominator, whether it be by way of trying to accommodate multiple form factors or multiple operating systems is certainly one of the biggest drivers of the decline of truly excellent software. One size fits all is never going to fit anybody even half as well as something more tailored to a specific subset.

I would like to see someone try the opposite, where when possible gaps in functionality on one platform or form factor are filled in, so all users’ experiences are elevated by the most capable target rather than dragged down by the least capable. That will probably never happen though.