Any idea why they do not simply publish safer cryptographic control sums for these downloads ?
The opposite question is why would they? This is all obsolete stuff and hosting it gains them nothing.
Does it includes Windows updates for older systems?
‘Microsoft no longer uses SHA-1 to authenticate Windows operating system updates due to security concerns associated with the algorithm, and has provided the appropriate updates to move customers to SHA-2 as previously announced. Accordingly, beginning in August 2019, devices without SHA-2 support have not received Windows updates.‘
The entire reason many of us like Microsoft is because they generally don't assume stuff that works fine is "obsolete" merely because it is old.
Perhaps for third party software but an operating system like Windows 2000 is obsolete because there is a newer, better version for sale and Microsoft clearly does not offert support for it.
There are older systems with custom hardware that continue to function, offline, using older operating systems. Some industrial and medical.
So what kind of support do you think Microsoft provides for these offline systems? Using downloads on their website?
Windows 7 extended support is available until 2023.
Yes, if you install the updates that Microsoft made available over a year ago, that enable SHA-2 support.
OTOH, they seem to use the word "legacy" for lots of stuff, both from them and from competitors.
Which is in several cases the best solution and much better than their latest offering.