There is not much of a difference between 65 and 67. It really just depends on the individual. Some people age very well and some don’t. Anyone can drop dead at any time regardless of age. The retirement age should be raised and the FAA medical system allowed to continue to screen as they always do. Additionally, Delta does screen for mental acuity during sims checks. Older pilots with dementia - younger than 60 - have failed check rides due to this reason. 65 is a random number. Some pilots should leave earlier and many do - some not voluntarily. The system, although not perfect, does work. Additional tests could be done if desired. There are tests, including MRI’s, to screen for virtually everything.
Our retirement is currently structured where, with proper planning, one can retire at a time much earlier than 65. Those who wish to retire can. Some who were caught in the transition from a DB plan to the DC plan should have the option of staying longer if they wish to and are able.
The retirement age could easily be raised to 67.