Thats a far fetched statement. Considering JASC was a single product line, while COREL has had it's hand in many areas of software development. COREL even packaged up their own Operating System years ago, which was later sold and is now known as Xanadros OS.
Corel makes some excellent plug-ins for Photoshop. Their KPT line is second to none.
What about their still surviving WordPerfect suite.
It's more likely that JASC PSP may not have been able to survive as it was. To develop to the ever growing technology you must have a lot of money to spend on development.
Then again, this is the way things are today. A favorite graphics editor I used was Micrografx PhotoMagic. It too was bought up by the biggest tech company around, Microsoft. Did Microsoft feel threatened by this company's product? Very unlikely.
To get to your issue. There is not going to be a simple solution. Oldversion.com does not provide you with every remedy to your software woes. The site is an archive. If you have a license you can find the software here. It's not the other way around.
There may be a slight chance you can find a CD version shipped with older PC's at computer shows. Or packaged with magazine subscriptions.
Otherwise, another solution is to use something else. Such as the Free Software/ Open Source editor, 'The GIMP'.
http://gimp.org/screenshots/