I’d just like to disagree with respect to the tyres, especially if you’re running MM/HD tubeless.
I’d be very surprised if they weren’t lower drag than a lot of commuting tyres, especially narrow commuting tyres, and very especially if the commuting tyres aren’t rock hard*.
The alfine (I assume running a manky chain) might have a bit of extra drag compared to a nicely maintained derailleur setup (I felt like I could feel the difference when I changed chain and sprockets on my fixed wheel I used to commute on).
(*definition depends on your weight, but probably 100-120psi)
Other explanations are different weather/wind?