Apple is a hardware company. iPhone and iPad work with non-macOS machines. For them to increase the market share they're interested in, it would be to sell more

Apple is a hardware company. iPhone and iPad work with non-macOS machines. For them to increase the market share they're interested in, it would be to sell more Macs, not have macOS on non-Apple hardware. I don't think there's a paucity of iOS apps by any stretch of the imagination. Any increase in quality iOS apps created on non-Apple hardware running macOS would be marginal, in my opinion.