Funny you chose 28 and not 30. And only two of those seasons have been in the last 6 seasons.
If you hold that 33 starts is a full season of starts in a 162 game season (162 ÷ 5 (every fifth game) = 32.4, so Stras gets the remainder) and that a full season of starts this season was 12, then Strasburg has missed 22% of his expected starts after his shutdown season.
The truth is that if Strasburg were in any other team, we would be laughing at the team that gave 7 years, 245 million to a pitcher that missed over 20% of his starts, was 32 years old, and has never been in contention for a Cy Young. We would be laughing hysterically and slapping ourselves on the back about how great our GM is for not being so desperate.
Sorry, you don't pay for aces to miss 20+ percent of their starts over their contracts, and you don't pay pitchers that do ace-type contracts
Stephen Strasburg in 2019 had 33 starts, 200+ innings, lead the NL in K's, and won every single one of his postseason starts, including a Game 6 start which, if he ages gracefully, will be on the front page of his Hall of Fame case. He won World Series MVP. You absolutely go overboard to sign that guy. And that is even before you consider it was the franchise's first World Series win, we sort of knew Rendon was gone, and it was a year removed from losing Bryce Harper.
The Nationals did what they had to do to keep him. I think they probably went $20 or $30 million too high (~10%), but there was no possible outcome where he could leave and it not be an absolute gut punch to this franchise. This is a business. Strasburg's representative knew his value to the Nats and only needed even passive interest from teams like the Padres, Phillies, and Yankees to scare the Nats into imagining a doomsday scenario of losing both him and Rendon.
I think it'll be hard for Strasburg to completely justify his contract on paper, but I'm looping him in there with the Zimmerman and Werth contracts. We want him to be a cornerstone and part of winning a lot of games, and still we know at the time of the signing there are off field realities driving the contract higher than pure production is likely to match.