Correlation doesn't imply causation, but every front office has different models that take every aspect of a player into account when they are considering extensions/free agents. That's one of the primary ways they assess future performance. In this case, they'll likely use a discount factor since the sample size is small, but within that dataset, the track record is still not great. You apply general aging curves to the already short stature he has, and Stroman is fighting an uphill battle to be valuable into his 30's.
I'm in the camp where they should absolutely sign him to an extension considered fair for both sides, but if his ask is well over that number, then it doesn't really make sense.