Look, iOS is the halo for macOS. Just as other Mac apps have far more breadth & functionality to their iOS counterparts, likewise, Files for macOS would work similarly to Finder with direct access to the file system. The look, layout, and naming would be made consistent with iOS. It would be a completely new app built from the ground up with Swift and all that goodness like Metal 2. It would shed the re-writes of Finder that's been bolted on and wallpapered over many times. The general populous would look more favorably at Files than Finder, in my opinion. After years of explaining and teaching new Mac users the "Finder," the Finder doesn't always click with most people & this can be a stumbling block.
Today:
"What's Finder?"
Future:
"Oh, Files is where my files are!"