But tell him he missing out,
Bino is clearly refering to his grandfather who walked out on his grandmother when he was a kid. The verse “I’m at my Grandma’s house” and the 3 lines that follow it is Gambino taking us into his time machine to his initial reaction to this happening. “But tell him he missing out” brings us back to future where he has obviously given some more thought about this event and it’s clear that his gramps done goofed.
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