Total time has ZERO to do with preparedness for the 121 world, and ZERO to do with whether one should pass a checkride or not.

By your logic, United should hire a 50 y/o who flew 5,000 hours farting around in his 172 in rural Kansas over the course of two decades, versus an F/A-18 pilot with 2,000 hours TT.

What matters is the quality of training you've received prior to coming to the 121 world, and the timeframe/quality of experience your hours represent--total time, age, and even specific airlines' training departments can't change any of that.

A 25% washout rate is not unreasonable AT ALL for people taking their first 121 checkride. A training department can only do so much to help people out--at some point people just need to acknowledge they aren't cut out for flying a jet in a 121 environment.

In any randomly-sampled group of 100 people with First Class medicals and ATP licenses, there will ALWAYS be a certain number of people who:

1) Lack the muscle memory, motor skills, comprehension of flows/profiles/limitations to manage a jet in a 121 environment

and/or

2) Lack the combination of motivation and cognitive abilities to remember flows/profiles/callouts, to execute them in a sim, and to deal with emergencies and work with other people in a cockpit environment

I am SO GLAD they are washing out 25% of new hires. This isn't an effing theme park for career-changers who want to play with a CRJ/EJet--it's an airline and people die if you aren't cut out for this type of work.