i feel everyone is sleeping on cap

i recently picked up this hero and started winning lot of games, i really love the run and punch playstyle he brings to the tank roster

but i see a lot of people say that cap is not good and is considered a throw pick, wats funny is that sometimes my team yells at me to swap to a shield tank while im playing cap, like isn't cap the shield hero or am i missing something here?

am curious to know wats the reason behind such sentiment?