That is a sufficient market to write applications for. The average number of units sold vary I think between 15 to 20 million (maybe more now) per year….

All apps that will want to continue to run will have to be ported over to Apple silicon. Rosetta will likely be removed in a few years.

If you consider that soon, every single Mac that is going to be sold going forward (except for maybe one more Mac Pro refresh) is going to be M1.

It is more about Mac units that will be running M1.