I drive past there if I'm going into the office (WFH most days fortunately) & a blind man on a galloping horse could see that problem coming! I kept expecting a new multistorey car park to go up in the area, but no, absolutely nothing! And, as you say, the road infrastructure isn't up to having 50k people all trying to descend on it at once.
On another note though, directly opposite the ground is a dodgy looking pub called, funnily enough, the Bramley Moore I bet the landlord there is rubbing his hands with glee! Other than a Chinese restaurant & a Subway there's not much else around there for food & drink without actually going in the stadium.