The fact that you reacted that way indicates that he's not actually as famous as you'd like him to be. If he'd described George Washington as a "famous-ish" general, you'd know he was being sarcastic.
I think this is e a cultural distance effect. I belong to a generation and live in a place where Liszt is part of the core. I recognise other places and generations may be different.
Back on topic, I always used to smile when I saw the Lisp interpreter known as Franz Lisp load up. Pity they re-branded it.
As an aside: did he just say Franz Liszt was "famous-ish"?!