Not maybe, it is really indeed a silly thought and nonsense, in my opinion.
Bubble and volatility is different, as well as fiat and Bitcoin. Bitcoin is the newest currency and revolutionary while fiat is just as old as earth. If Bitcoin was just a bubble, I think after bursting (deflating) it wouldn't have a huge comeback just like what's happening in Bitcoin every time its price decreases a huge one. Also, inflation doesn't exist in Bitcoin, and the most impossible thing to assume is that Bitcoin is just a Ponzi, that's too hilarious.
It wouldn't live too long if it is just a Ponzi.
I wouldn't say that he is silly, I would just think that he is a willfully ignorant person, those are different things. A silly idea would mean that someone is researching every option, you do not learn about fire being something you should not touch without touching it, someone did that once upon a time and now we all know it, it is human nature as well but some people definitely did it for us to learn the consequences. Silly things could happen, it is just the way humanity grow bigger and wiser.
However if you are willfully ignorant and you do not want to accept the truth even though it is there, like saying people warn you touching fire is bad, they bring you someone who has touched it before and burned their hand and shows scars, and you still go around and saying "I think touching fire could be fine, what do you think" to people, that is not just silly, that is ignorant.