Your Average Joe would be confused when they see the error description. And if it has one of those good-on-paper/bad-in-practice phrases like “contact our webmaster” it’s even worse.
They’ll start calling you or writing emails, thinking that they’re helping but the conversation is something like:
I’m trying to buy a sweater for my grandkids, there’s 5 of them. Jimmy is 6 years old ... So when I got to the sweaters page I typed in: “turtleneck”
Then they start asking — no, DEMANDING, explanations they won’t understand. So how do you explain to Joe that you were in the middle of a DB migration?
And even if you just have a bot answer his email or whatever, then why did you even bother writing the bot if it’s not a human reading it?
So I think oftentimes the best solution is a cute lil dino saying “try refreshing, and if not, go to our homepage and try again.”