> It's usually not that much - typical executable is usually several megabytes in size and many processes can share the same code memory pages (especially with shared libraries)

Have a look at Chrome. Then have a look at all the Electron "desktop" apps, which all ship with a different Chrome version and different versions of shared libraries, which all can't share memory pages, because they're subtly different. You find similar patterns across many, many other workloads.

Or modern languages, like Rust and Go, which have decided that runtime dependencies are too hard and instead build enormous static binaries for everything.