The comic doesn't say anything about what hash function to use. At any given time you could identify a hash function which takes a millisecond per password. That will be the hash function to use for the comic's algorithm.

The point of the comic is that a character salad is both less secure and harder to remember than four random dictionary words. That's no less true today.

The MD5 hash of "correcthorsebatterystaple" might be trivial to brute-force today, but it is - and always will be - harder to brute-force than "Tr0ub4dor&3", even if in both cases the attacker knows how you generated the password.