The issue in that whole proposition lies within this one single sentence
Business software is written for windows
Nowadays, practically all companies are moving towards either SaaS, or in house web services. The pandemic has killed native enterprise apps, for better or for worse.
Windows only has decent presence because it's reasonably easy to integrated Windows machines into corporate structures. The moment Apple taps into that market, it's all over. We've seen that with Google basically ruining the school market for Microsoft by doing that, and it will happen again.