They are certainly experimenting with which features might make sense on the "other" OS. But until your post, I had almost forgotten that the launcher still exists on macOS. Likewise, Dashboard still exists, but does not get much attention any more. But even with the new iOS giving more "desktop" powers to the iPad, Apple still seems to aim for a UI model quite different to macOS. So this seems to be intended.

That launcher may be indication Apple was thinking that way, but look at their latest U-turns on pro hardware and reinforcing their commitment to laptop/desktop. I don't believe they're going that way anymore.

Also. Did you ever see anyone using that launcher as primary interaction?

They more-or-less tore down the wall when they renamed the company from "Apple Computer" to just plain "Apple."

I'll be surprised if they're still selling Macs in 5-7 more years.