Exactly this is why current copyright rules are BS. Having multiple studios with pressure from competitors results in better games (and less micro transactions shit to sqeeze franchises to death)
... I'm imaging the natural extreme conclusion to this. There are 16 sequels to masseffect and you need to research which games you need to play before you play the newest one. This also leads to conflicting cannon and infighting
It's not a coincidence it happened on the same day. After the first studio did their announcement the others kind of had to come forward to lay their claim.
People tend to think of digital things as unchanging and permanent but that isn't really the case. I'm fascinated by the concept of bit rot and other ways that digital things can disappear or degrade over time.
It's good that flash is not still an essential part of the modern Internet but its death did firmly cut off an entire era of Internet culture that cannot be experienced in quite the same way.
The official Homestuck site will still let the original SWF files load as long as you have something that can play them. Ruffle works fine. You can also use one of the few browsers that still supports PPAPI plugins (like Falkon) with the official Flash plugin.
But personally I'd say to just use The Unofficial Homestuck Collection, which is more pleasant to read through than the original ever was.