26 is also the age Drogba got into Chelsea after one single high profile season in Ligue 1.
I'm not syng he's going to explode like Drogba did but age doesn't always mean everything.
It's true (except for the one single part, he'd had two Ligue 1 seasons with over 0.5 gpg). There are late bloomers in this sport, and to me it's totally conceivable that Gyokeres is one. He was extremely good in the Championship and has been even better in Portugal.
I have a hard time assessing players who are spectacular in the Championship. A lot of players who seem too good for that level and not good enough for the PL (Pukki the classic, Mitrovic is the rich man's version insofar as he is a good PL striker but looks like f***ing Van Basten in the Championship).
The last time we discussed Gyokeres here someone raised Ivan Toney, who also had no top division experience until his mid-20s. My response then was "I would hate it if Chelsea spent 70m on Ivan Toney right now." Late bloomers at a non-top level are extremely risky. But you're right, sometimes they pay off something major.
I'm currently extremely enjoying the late bloomer arc of Dom Solanke, because it's so fascinating to me that he was simultaneously the precocious prospect who was seen as top of his year throughout his late teens and then ended up coming extremely good in his mid-20s. For years he seemed the epitome of a "too good for Championship, not good enough for PL" striker, and suddenly he's turned on the goals. It's not often that the late bloomer is also someone who was seen as the next big thing.