Surprisingly, no, or at least it's not common.

I'm from a country that has 6-digit PINs on most cards, and I've traveled to e.g. the United States where people are surprised that credit card PINs can be more than 4 digits, but in my experience, terminals accept them just fine. It seems like they are designed to suggest a PIN is only 4 digits but they will happily accept more. So while you're entering your PIN, the display looks something like:

    [....]
    
    [*...]
    
    [**..]
    
    [***.]
    
    [****]
    
    [*****]
    
    [******]

And then you hit OK and the PIN is accepted.