Wow, that really isn't as funny without audio.

True, but even once they convert the back catalog, you lose all the cool interactive elements.

While I have access to legal MS DOS 6.11 licences, it's not something the retro computing crow seems to care too much about.

Lots of people bought these when they where up-to date and most aren't interested anymore. You can get these for free from plenty of people.

The fact that windows xp needs to be activated in contrast to dos makes it bit more tricky, but cracks are aviable and legal 1) if you do indeed own a licence.

1) As for every legal discussion on the internet: Different places have different laws. However, I don't think MS cares about XP at this point. In contrast to DOS they don't sell it anymore.

That difference only exists because said Flash games were first and foremost published online, and because the Flash heyday is offset from the DOS heyday by about 15 years. Just because they happen to still be floating around on Newgrounds or Gopher Gas or whatever other Flash game site doesn't mean they're actually cared about necessarily. Ultimately, the difference doesn't matter: just like how DOS game developers ended up migrating to Windows, Flash game developers will end up (and indeed already are) migrating to HTML5. Few people lament the DOS games that weren't ported, and in the long run, few people will lament the Flash games that weren't ported (or, if they do, will port them themselves, as was the case with multiple DOS games, the prodigial example being Doom).

That difference is also less meaningful with companies like GoG reselling older games, often with the necessary emulation layers for them to run on newer Windows versions (and - lately - Linux). Thus, even some very neglected DOS games are still in distribution. Hell, Super 3D Noah's Ark of all things is on Steam. Super 3D Bloody Noah's Ark. If that manages to be the case, then I'm pretty sure Flash gamers have nothing to worry about in the long run.