Corbin repeated his breakout 2018 last year so he'd definitely get more than 4/$106M
Also, out of the guys you mentioned, cueto and arrieta are both trash at this point. Darvish is having a good start to 2020 this far but hasn't been inspiring in yeeeeeaaaars (plus only one season of 200 ip all the way back in '13). And wheeler had Tommy John and has a worse track record than corbin
Yeah? What 31 or older year old pitchers have gotten 100+ million and a $25M+ annual value, ever? Well, here's the list:
Strasburg
Greinke
Darvish
That's it. Strasburg's contract looks like a potential albatross and you just took the position that Darvish isn't working out either.
Here are their ERAs in the years that led to those contracts:
Strasburg: 3.32
Greinke: 1.66
Darvish: 3.66
Corbin was at 3.25 last year and he's at 3.99 so far in 2020. So right now his ERA is nearest an albatross contract (Strasburg) and Darvish, which hasn't gone well and was for $5m less in annual value (based on last year, his age-30 season's, ERA). Based on this year? He's at a 4 ERA, a third of a run above a guy who got $5m/year less on a contract you admit hasn't been good for his team so far.
And as Slate said, there's a reason guys generally don't get paid a lot for these stages in their careers unless they are significantly better (Greinke) or selling them at the same time as prime years, and it's the point you just made: pitchers decline. Yeah, he
might get 4/106, but he's not getting much more, if any, which means the contract isn't an asset and you're not getting much in trade unless you eat a lot of money. For example, Greinke was traded in the middle of that contract, and he's a freaking monster. In order to get significant prospect value, the DBacks had to eat $10 million/year in salary on fewer remaining years than Corbin has.
Now, note the problem with what I assume you're reaching for in this argument: Darvish doesn't belong on the list. His contract is too small. Does that make you feel better or worse?