My laptop charges with USB C, so when the standard charger broke, I just used the USB out port from an EcoFlow battery. The display on the battery said the laptop pulled 25-30 watts while charging. So, why can’t I use just any USB brick that can output more than 30 watts?

Is there something that is bound to go wrong that I don’t know about?

Are laptop chargers really that special?

(Edited for clarity)