Allow me to demonstrate what shapes look like:
View attachment 1813742
The fact that you had to boost the contrast within each icon here kind of argues against you. The underlying shape of each one is still a rounded rectangle. Some have good, legible contrast within that, some don't. You made a row of perfect-contast versions of each one to illustrate your point, but they don't all have that much contrast. And yeah, we still have color to differentiate but if we're arguing about variably outlined icons versus "tiles", the tiles all mush into visual sameness a lot more easily than icons whose outlines are different.
I don't happen to think this is a huge issue on MacOS, as there are many other ways to launch and interact with apps than hunting down, recognizing and clicking on their icons (app launchers like Alfred or Spotlight or Launchpad, for instance -- all of which rely more on typing the name of the app). It's sort of boring, though, and I definitely would disagree with "shaming" an app that doesn't use a tile icon.