I'm not saying Porcello is as good as those pitchers, just pointing out pitchers that peaked later in their careers.
Porcello's first excellent season was in 2014, at the age of 25. Those other guys didn't put it all together until age 30, age 28, age 29.
The Red Sox organization screwed with Porcello's approach, and it hurt his development. I'm fine with him going back to the sinker and low strikeout numbers, with an ERA in the 3.80s and 3 WAR a year. He is working on it, but it hasn't been easy for him to do mid-season.