Diamond Joe Quimby
A$AP Joffrey
He had a 122 wRC+ as a 17 year old. Age matters here lol he was the youngest player in the league. Put him in full season ball next year see how he does and him breaking into the league as a 20 year old really isn't that crazy.
Indeed, age matters. -4.1 years younger than the average league age does provide for some upticking in the numbers (122 wRC+, .366 wOBA). However, I submit to you, oh whimsical stranger...
Rafael Devers, whom has been used as a proxy for Guerrero by several (better hit, lower power tool grades) was 17 (-3.9) in GCL and had a wRC+ of 146 (wOBA of .405). He then skipped A- the next year and did his full season of A-ball at 18. Then he did his A+ this year at 19. He will not be in the majors at 20 barring something ridiculous occurring, and that's with things going quite well for him.
It is quite crazy to see him "breaking into the league" at 20 because it would require him to skip at least two full season levels. Unless you believe he is Miguel Cabrera level good...which judging from the last couple pages, some people do.
But yes, "lol".