You’re a Somewhat Nebulous Term
We’re not exactly sure what’s going on here. All we know is that the OP had to use a specific phrase—statistically valid—when sending a request to potential vendors. One of the vendors took it upon themselves to point out the ridiculousness of the phrase by using a ridiculous phrase themselves. “Actually, ‘statistically valid’ is a somewhat nebulous term.’”

Who in the world uses nebulous unironically in a sentence? After reading the unnecessary comment from the vendor, the OP decided to turn it into an (anti)motivational poster. We pray the vendor got to see the poster. Nothing shuts down a mansplainer more than letting them know they’re in the wrong.