The line comes from SpongeBob SquarePants, the long running animated television series, where formal narrator and announcer voices are a regular comic device. Clipped on its own, the interruption began circulating on soundboards and in meme edits as a ready made break in programming. It sits alongside other long running SpongeBob quotes like the my leg gag, which fans reuse out of context for years. Its popularity comes from that reusable format, since any creator can place it before their own announcement and borrow the show's deadpan timing.
About this sound
SpongeBob announcer saying we interrupt your bleak and meaningless lives, a deadpan TV interruption clip used for dramatic breaks and meme edits.
A flat, official sounding male announcer cuts in with the line we interrupt your bleak and meaningless lives, delivered as if it were a perfectly normal broadcast notice. The joke lands in the contrast between the polite interruption format and the bleak insult aimed straight at the audience. There is no music or build up, just the dry voice taking over the moment, which makes whatever follows feel suddenly important and completely ridiculous at the same time. It pauses a video cold and resets attention instantly.