LOL you and me and lots of others, I think.
Lots of folks have old legacy FPGA designs they inherit from some past designer that left the company and now they need to make changes.
But the software tools left with the designer, and weren't archived.
Altera left all the old versions online on an as-is basis. Nice.
Intel likes to make things disappear as soon as they go EOL. Not so nice.
EOL for Intel does NOT mean EOL for users.
I have made a habit of downloading the full install for any tool I use and then archiving the install tools on a backup media.