I've had mild to moderate Crohns for 34 years. Personally, my 'typical' Crohns symptoms (cramping, uncontrollable diarrahea, bloody stools, etc.) have improved over time because the medications have improved and I've gotten smarter about
how to better control the disease. My flare-ups are much less frequent (like about
one per year, versus nearly every month in my teens and twenties). On the downside, I have several Crohns side-affects (joint pain, fatigue, neuropathy, depression) now that I didn't have 20, or even 10, years ago. Also, it takes longer to recover from those occassional flare-ups, probably just because I'm older.
I think people with moderate to severe Crohns who have had surgeries would have a different story to tell.