Microsoft themselves offer a freely downloadable software compatibility tool which internally contains a full Windows XP virtual machine. There's instructions online for how to import the imagine into Virtual Box.
I wonder if it has to do with the common practice of using a stripped down windows install as a live bootable environment to run recovery tools?
Even if you have a licensed copy of WinXP, MicroXP is useful because it is a stripped down version that has been tested. That represents quite a lot of work.
You can get a ton of old, abandoned, or unsupported, software from Archive.org. I have no idea if the original authors are aware of it but if they are they don't seem to care that much.
Everything on archive.org is user uploaded. So I think authors don’t event know. I just recently uploaded an old Pocket PC / Windows Mobile game that I found on an old disk drive. It took me less than five minutes to register and upload it and it was immediately available.
It's not that, archive.org has a DMCA exemption for being a library. It makes it legal for them to host the data, but that doesn't mean it's legal for you to download it. Weird I know... I mean why else would they store it if it's illegal to access? I've never gotten a straight answer to that.
> I mean why else would they store it if it's illegal to access?
It's not permanently illegal to access. In the US, there's a constitutional requirement that copyright and patents be time-limited, so eventually all that stuff will be public domain. And the copyright period is current so absurdly long that by the time XP is public domain, it will be hard to find outside of dedicated archives.
An ordinary library can not scan a copy of a book and allow unlimited downloads of that scan from the web. The DMCA exemption doesn't allow that. Actually, archive.org got in trouble pretty recently because they were accused of doing almost just that. Their response was not that they had the right to do it but rather that they had never been doing it to begin with - that each copy given out was merely "lended" and backed for the duration of the lend by an actual physical copy in a partnering library.
Similarly, you will find a bunch of copyright software on there, including for recent DRM-free and cracked video games. Unfortunately, my impression is that the archive managers simply do not care about copyright. Anyone who wants to get something they own taken off the site has to put in quite a bit of work, similar to the old wild-west days of YouTube.
As far as not caring, Jason Scott has said himself that they take a "ask forgiveness instead" approach because getting permission is too difficult and time-consuming. In 2016 they were adding 15TB per day with a total storage volume of 30PB, and by 2020 that total was 70PB.
https://archive.org/details/MicroXP-0.82
As for piracy, it seems Microsoft just don't seem to care. MicroXP has been on Archive.org since 2019!