On one hand, yes, he's a deeply flawed coach so it feels kinda good to see him extended. On the other hand, most of the other NFL coaches are somehow worse, so his replacement is statistically likely to be worse than him.
UrinatingTree probably has steam coming out his ears but realistically speaking, Tomlin came in with the Roethlisberger core and might as well stay the course, at least until the time comes to finally replace Big Ben.