What was closed about Windows was the source code for the kernel as well as libraries and APIs. As a very strong supporter of Free Software, this was a huge part of what I railed (and still rail) against.
In terms of the ability to run random bits of code on it, Windows was highly open. Perhaps too open when you take into account not only malware, viruses, and spyware, but the various crapware/bloatware OEMs would pile onto their Windows preloads.
Arguably some Linux distros, with their comprehensive archives, though with rules for what could or couldn't be installed (based on licensing requirements) were more "locked down", though in truth you're more than open to install third party from sources, as binaries, or any other means you care. In practice, I prefer sticking largely to my distro's own archives and installation tools, precisely because the software is both more vetted and generally behaves far better.
In terms of the ability to run random bits of code on it, Windows was highly open. Perhaps too open when you take into account not only malware, viruses, and spyware, but the various crapware/bloatware OEMs would pile onto their Windows preloads.
Arguably some Linux distros, with their comprehensive archives, though with rules for what could or couldn't be installed (based on licensing requirements) were more "locked down", though in truth you're more than open to install third party from sources, as binaries, or any other means you care. In practice, I prefer sticking largely to my distro's own archives and installation tools, precisely because the software is both more vetted and generally behaves far better.
So, no, your criticism really isn't valid.