The only way that the age of the Boeing will come into play in the investigation is if the flight crew's lack of situational awareness was brought about by having the older analog gauges instead of a more modern glass cockpit presentation. I once ( 20 years ago )had to make the transition from the Airbus 310 back to the steam gage B-727. It is a difficult transition, and if you add outside factors - thunderstorms - possible nav problems - whatever, I can see crew overload as a factor.
I have over 3000 hours in the 737-200 and I would fly one anytime, anywhere.