I think there is also some competition with the iPhone SE. Even though the Mini is not intended to be a budget phone, it is 100 Euro cheaper than the non-mini. So, I can imagine a chunk of people would buy it for its lower price if the iPhone SE didn't exist. Even more if you consider that the Mini actually has a larger screen than the SE.
I really really want a Pro Mini :(
I feel like my plan right now is to hope with the iPhone 14 launch, the 13 mini will continue to be sold with a price drop, and then I'll upgrade my 12 mini to the 13 mini and get the battery improvement. I love the size of this phone and hope I'm never forced back to the gigantic "normal-sized" phones that we've gotten stuck with the past decade.