Lots of experienced pilots do miss out because many airline HR departments do not see past certain criteria:
(i) Either you are a cadet with minimal hours and a willingness to effectively have a mortgage (SSTR) without a house at the end of it,
or (ii) you have for example 2000 hrs total with 500 hours minimum on a medium jet (RJ, EMB 145 etc) and ideally on type just to get an interview.
There is a huge gap in between those "requirements" that is often ignored since the demise of the 700 hr self improver route. People who can actually fly aeroplanes in highly challenging circumstances have a much harder time getting well paid flying jobs than those with a small fortune to spend.
Pilots who have 1500 hrs instructing or 3000 hrs flying light twins/air taxi work and are perhaps older than 25 really find it very difficult just to be considered. The best chance for folk in that boat is to be interviewed by company pilots who recognise the value of their previous experience and their perseverance in gaining it.
Airline pilot demographics dictate we need all levels of age and experience.