Regardless of a movie or TV show's overall quality, you can generally bet that it has a small army of talented people working extremely hard to bring the director or producer's overall vision to life.
And when that production is aimed towards depicting real people, we can sometimes see this army working almost literal magic to capture the details of how those people would have looked and acted. It doesn't always work out but sometimes the resemblance can be almost eerie, as was the case with Charlize Theron's role in Monster or Jamie Foxx's portrayal of Ray Charles in Ray.
But whether an upcoming role for Seth Rogen has him looking like his subject or not, we can say with total confidence that he won't just be playing himself.