I'm curious why the selectors have persisted with bringing Overton in from the cold over the last 5-6 years. He's not a kid anymore and he's pretty ordinary.
I'd rather give Mahmood a go who will swing the old ball and is a bit quicker.
He went on loads of England "bowler training camps" or something like that, with some kind of development contract. So they've invested a lot into him. Plus plenty of time training with the team as part of the squad but not selected over the past few years. I recall him saying the coaches wanted him too add more pace, which doesn't seem to have been hugely successful. He has however had as good a bowling average as anyone in the past few seasons in the Championship, and the "he bats a bit" angle probably helps. Although his batting has looked tumescent for England. He bats at 6 ot 7 sometimes for Somerset which is a pretty damning reflection on the Championship. I don't think he's done any worse than Woakes though who has had numerous tours overseas and consistently averages 50+ with the ball.
In terms of age, he's still pretty young in test terms. It's rare for a cricketer to play top level for many years, but there are a ton of players who in their peak of late 20s early 30s and step up from county standard to test standard for a short while. Players like Sidebottom, Onions, Tremlett etc, county bowlers who suddenly had a few good years at test level later on. So there's some logic. Cricket is so much more tactical and psychological than physical compared with football so it makes sense that experience and maturity plays a bigger part. I'd be wary of throwing youngsters in too soon generally for that reason. The likes of Root, Stokes, Anderson, Broad who play internationals from early 20s well into their 30s is the exception rather than the norm. Plenty of times over the years England have thrown young players in then discarded them. As a couple examples, James Vince and Sam Robson both played in their early-mid 20s, did average to poor and were dropped for younger options (who have done as bad or worse, in fact Robsons average of 30 is better than the multitude of openers we tried since). The irony is they're better, more consistent players now than when they played test cricket. The aim for most players, who aren't Anderson or Root calibre, should be to ease them in and help them develop in their mid 20s, and then give them an extended run in their peak years from late 20s on. Now, Mahmood may well prove to be like Anderson or Broad and prove himself immediately and become a consistent test performer but, cynically, statistically he's more likely to fail, damage his confidence, get sent back to the Championship to work on his game, and when it clicks for him he'll either be overlooked for a younger prospect, or will have lost focus on red ball cricket to pursue the money available in franchise cricket.