There's plenty out there that punch above 11%.
Here's an impressive imperial stout from Estonia :
https://puhastebeer.com/shop/beer/epicus-bourbon-ba-imperial-stout-15-7-50eur
(The team at Puhaste, and another called Pojhala, in Estonia, make some impressive brews)
Haven't tried that one yet, but have others from the same brewery/style that sit in the 13-15% range, and quite a few from other places.
The strongest I have on my list is from BrewDog. It was called Tokyo, a big imperial stout with 18.2% of
warning warming goodness.
I'll be in Amsterdam in 3.5 weeks, I'm gonna look out for Elfde Gebod