In most vocations there is a birth of the XYZ profession, growth, plateau, decline, and finally demise.
Your career earnings will have the highest potential if you can time your retirement as the vocation growth curve starts its break to plateau.
Consider the following civilian aviation jobs,
Navigator... demise
Radio Operator... demise
Flight Engineer... serious decline
Pilot... plateau-decline
UAV... growth
You need to evaluate your time to retirement. A 65 year old with a FE rating that finds one of the last FE jobs and wants to work one more year... It might be feasible to take the position.
A pilot, 50 years old in the middle of a career can ride it down for the next 15 years as the decline accelerates. Not optimum, but possible.
An 18-20 something looking for a career to span the next 4 decades needs to look further out and determine what is in the beginning of a growth curve. Like it or not UAVs are in growth.