Is it dated? Yep, but it's intuitive enough for nine-year-old tombert to have figured it out ok, and to me part of the fun is trying to use the UI quickly enough to put out fires and the like.
It could just rose-tinted glasses on my end, very likely honestly, but I still find the entire experience to be pretty fun. I liked Sim City 3000 and Sim City 4, and they are arguably better games, but for me Sim City 2000 hit the right balance of "easy" and "complicated" that I find myself most drawn to. I will load up Sim City 2000 about once a year off of my GOG purchase, and still thoroughly enjoy it, and find myself wasting way more hours than I budgeted for it.