This was exactly what Microsoft tried to do with the Surface Pro and Surface RT. The Surface RT hardware was very well made, however it only ran Metro-style Windows apps, so the only piece of big-name software for it ended up being Office.

Apple does have the scale on its app store to force developers to change over to ARM (say, if they announce ARM computers a year before they are for sale), but at the PPC -> x86 switch, Intel processors were more powerful than equivalent PowerPCs, allowing Rosetta to bridge the gap. This is more difficult (but not impossible) with ARM processors.

Also, if all of the computers are ARM, you lose out on virtualization, which is a biggie for many business users.