If we are gonna argue Sasuke won't open with Genjutsu, then Minato certainly isn't opening with sealing. And Minato still has to use the seals and whatnot and set up the teleportation, Sasuke's EMS grants him pretty much precog, so he should be able to react before Minato teleports (aimdodging the tp if you will). Sasuke's arsenal is just better, between the two power ups (Susanoo and SM) Sasuke can enter his far quicker, between the hax Sasuke's is far better, and in raw stats Minato is only a possibly High 7-A but Sasuke is concretely High 7-A. Not to mention, Minato has no resistances to Sasuke's EMS hax listed on his profile, meaning there's nothing to say Minato can defend against Sasuke's EMS.
EMS Sasuke takes this with his near precog to counter the teleportation via predicting where Minato will go, plus hax that Minato doesn't resist.
My point is that if you're gonna assume Sasuke will instantly use something out of character, Minato can too. So it's a stalemate on that point.
Setting up teleportation takes no time at all.
He can literally spred dozens of kunai with a single flick of his wrist.
The point of FTG was literally to counter the Sharingan. The Sharingan precognition works by reading the opponents' movements, which you can't do when you disappear completely then reappear at another random location. Just look at Izuna's attempt at "aim dodging."
This is how long it takes Minato to enter SM.
His SM activation is literally faster than Kamui (because he threw a kunai prior to entering SM, and you can't move while gathering nature energy, meaning he only started the process after), and Kamui can blitz Obito.
So SM is nigh instant for Minato.
And if we're talking about speed, in SM Minato has a solid speed advantage, and in Base his reaction scales to a higher relativistic character (Juubidara and 8th Gate Guy) than Sasuke (Unstable Juubito).
Ok I changed the OP to say they're High 7-A. Don't want people claiming Sasuke will just stand there and tank a Sage Rasengan with no damage.
Minato doesn't need to resist the genjutsu to break it afterwards.