Sunspark What I think is although Microsoft allows its software to be downloaded from its servers, it doesn’t condone third-party distribution and it might be forbidden based on copyright law. Some sites have received DMCA takedowns for linking to Windows ISOs. Now in the cases I found it was for altered or leaked ISOs but I think this is only because Microsoft, for the most part, doesn’t bother, but that doesn’t mean they couldn’t. I could be off-base but I figured it’s better to be safe.
Especially when it comes to special enterprise editions which are not normally available from Microsoft, that small risk is higher.