The Rising of the Shield Hero - Captain A has entered the chat.

I mean if even GOOFY can fight using a shield…

The main reason they hate the shield hero is because of stuff separate from the shield itself, however the kingdom's people are still morons for disregarding it.
In fact, a side aspect of this series is hammering home the fact that, no matter how good your DPS is, a good tank to protect you is an absolute necessity.