I'm an IGH convert who I think has just flipped back to the derailleur camp again. I have a 2013-ish Montague with a Nexus 8 that I love, but it lacks the gear range for the steep hills here. So I've been looking at more performant ones, but I want to be able to lock up the bike, which rules out Rohloff. I also want drop bars, which rules out the Enviolo (which at 380% gear range is still kinda at the edge of what I'd like for the hills here). So the Alfine 11 is the only candidate, but word-of-mouth is that they're less reliable than I'd like...

I also just got a rear flat the other day, which reminded me how it is more of a pain with an IGH. I was able to slide the tube in without detaching (or even misadjusting) the shifter cable, but... still. It also makes keeping multiple wheelsets much less feasible, which I'd like to do as a compromise to avoid needing to have more than one bike to do both roads and gravel.

I guess what I'm coming around to is the difference between "low maintenance" and "serviceability". An IGH (particularly with belt drive) needs no routine maintenance, but servicing it is a big hassle. A derailleur needs regular cleaning/lubing, but, any part that wears out or breaks is one I can easily replace myself. Now that I don't commute and I live somewhere it's trivial to hose down a dirty bike before putting it away, the routine maintenance seems fine, and I'd rather have a bike I can fix myself no matter what happens. If I weren't intending to sometimes (and super securely) lock up the bike in public, the alternative of saving up for a Rohloff would probably have me undecided again.

That said, I have an Enviolo and Gates belt on our family e-trike and it is fantastic there.