There comes a time when you realize that you will never be aboard another one unless a museum gets one and opens the interior up to visitors.
My last time on a 717 was in 2016 aboard N926AT, formerly N411TW
The same goes for me aboard an Airbus A318, last time being last month. Air France only operates 4 now and soon will be zero.
It's also weird when the time comes, but you don't know it. Despite hundreds of MD-80 flights, I never boarded one knowing it would be my last. Covid came and they were gone just like that.