As you get older you become aware your views are hardening and closing off to new ideas. you become aware when you start rolling your eyes - "thats what the kids think." I believe intellectual quality just like the quality of every other function is regulated by input. Creating routine help improve habits and there are ways of breaking out of bad intellectual habits. Work in coffee shops to be around people of all types and make it less serious. travel a lot to remind yourself what the rest of the world is like. take long walks to allow your thoughts to prevent thought congestion allowing it to spread. go on nature trails to reset your mind to other elements. dogmatism builds up in the residue of years by act of homogeneity.
I also fear that such intellectual flexibility becomes a way of protecting broader and more hidden edifice, its a kind of hidden desperation or even pessimism embedded in certain type of flexibilities. something to be said about erecting rigid structure which people do when they are young and then it could be toppled and people become more flexible, wiser, more willing to revise. i worry that its deeper dogmatism than erecting dogmatic structure that could be toppled.
its not the similarity of routine with younger age but the awareness that come of our susceptibility to dogmatism that alters the experience and I wonder if such routine could be of much help.