Here is a conversation from a "BBC Learning English" YouTube video:
Feifei: We sometimes put the word "straight" in front of "fire". "Straight" here means "very".
Roy: So I probably should have said your T-shirt is straight fire, then.
Feifei: Only if that's what you really think!
Do that sentence in bold mean "If you say so"? Or is there any other way to say that more naturally?