3 years might be a stretch. They were in the Cotton Bowl and a top 10 team in 2017.
Problem is that recruits viewed Helton as a dead man walking after 2018. It's not when the fanbase says "fire the coach" that you have to fire the coach. It's when recruits say it.
For instance, a lot of Clemson fans wanted Dabo fired back in 2010, but he had a top 10 recruiting class. Turns out the recruits were right about him, which isn't always the case, but IMO it's the real indicator of when a coach should be fired. And I have nothing against Helton, but the recruits said he should've been fired last year, and it doesn't appear they've changed their mind this year.
At this point, Helton could be one of the best coaches in CFB, but if he's recruiting at the bottom of the Pac-12 at USC, he's dead.