Yeah they do. Crazy money. I've had a 01 and a 97 xj and they aren't made any more/ but they want as much or more now for them than what I paid for mine 17 and 14 years ago respectively.
That was the reason why I bought a Durango 10 years ago.
I just bought another Durango (same body style as my first) and had to pay more for a nice 03, 2 weeks ago than what I paid for my 01, 10 years ago. But not at the extent as the xj's now compared to them.
It doesn't help that I live dead smack in the middle of salt country. I did have to go 4 hours away to find a clean Durango, that wasn't far enough for a nice xj, this round.
I got my first Durango at 1/3 the money an xj was in 2013, this time I had to pay 1/2 of entry price of another xj for my 2nd Durango. From what I see a "nice" xj can't be touched below $6k, just like back in '13. I don't have that kind of money for a vehicle.