Not really - most people (including me) wouldn't care about an unoptimized macOS interface on their iPads. It would be sufficient if the apps that I am using were optimized for the iPads regarding touchable area, scroll etc.You would need to fully redesign the interface. A straight MacOS on a touch device is a horrible idea.
That would mean minimal effort from Apple and only effort from app studios to make their app ready for "macOS on iPad". However, as Apple always tries to make the impression of a perfect company without flaws, they would never green light such a project without making the macOS UI ready for it. This however won't happen soon because the target group of people who can make use of macOS on their iPads is tiny.
So in short, Apple wouldn't have trouble doing so, but Apple is too "arrogant" to ever do this.