Many poeple took it literally saying that Naruto >> Minato and blah blah crap.
However after today's chapter we got the confirmation that Minato indeed posses the "Perfect" sage mode unlike Jiraya and similar to Naruto.
but Fukasaku was talking about Naruto's SM being superior. But how is Naruto's SM superior to Minato who also posses the "perfect" edition of Sage Mode? well
Naruto was 1-step ahead of his dad with the Shadow Clone backup for extending the SM! That's how Naruto surpassed Minato in SM according to Fukasaku