That 4MiB per application assertion is not true of OS/2. 4MiB was minimal physical RAM requirements for 32-bit OS/2, which I myself ran on a 4MiB machine for a

That 4MiB per application assertion is not true of OS/2. 4MiB was minimal physical RAM requirements for 32-bit OS/2, which I myself ran on a 4MiB machine for a while, but it did not scale up from that by number of applications run, let alone by number of 16-bit applications.