PIN isn't particularly vulnerable to brute force anyway, as number of failed authorisation attempts is strictly limited to something like 3, and a fraudster has to risk capture by being physically present at each attempt or 'trying out' a stolen card, and having their face recorded on cameras.
I haven't seen any advantages for using 6-digit or larger "passwords" for that particular scenario. The largest practical security benefit seems to come from enforcing random PINs and not allowing to choose - since the banks that allow to choose are vulnerable to "dictionary attacks" of trying the user's birthday (obvious from other stuff in a stolen wallet) and stuff like 1234.
Now, checking "signature" instead of chip&pin, now that's an example of blind trust.