It is. That's you flanking properly, and them not having map awareness.
Planetoverwatch has Roadhog listed as "C-tier".
Metabomb has him listed as "tier 3".
Ten Ton Hammer has him as "A tier", but they have an "A+ tier" where Rein and Zarya are ahead of him, and an "S tier" above that.
Is there a hero ranking that I'm overlooking that you'd prefer I use? No ranking I know of considers Roadhog to be "overpowered". He has a strong niche, but has a ton of weaknesses, and provides very little (read: zero) team support other than being a target and getting picks.