Training ATCOs isn't like training a McDonalds Burger flipper* - it takes years of time & resources. I can't see how some sort of age limit can be avoided, if not purely for common sense!
Imagine (an example that may or may not be realistic) joining CATC age 50 (and being just as bright as someone at age 25 say), fully valid age 53, retire at 60. Thats a
load of cash per year outlay in training costs for a short time at the front end.
Maybe the age limit needs moving up 5 or 10 years?
RS
*Other quality fast food outlets are available...