I upgraded to 15.... don't know why... It mentions using cd architect.... manualI'm sure that's not coming back.

What's a CD?

No, CD Arc is no longer included or can be purchased through Magix. Later versions of Sound Forge have the same capabilities built in.. but it is no-wheres-near as intuitive.
I would surmise, text from the legacy manuals or 'help' were used and remain.
AFAIK, If you have an old version of the CD Arc software, it is still possible to activate it with a valid serial.