Seeing how Rust is consistently at the top of Stack Overflow's most loved languages, I'd wager it's gonna be Rust again.
Next year is not literally next year.
Over last decade and a half it's been: Ruby -> Node.js -> Go - > Rust and something new will come along. But just like others on the list, they will all live and evolve together.
Ruby and Node are, for the most part, not playing in the same field than Rust. I have absolutely no problem seeing them living along each others for decades.
Longshot bet: It will be something old with a surpriing new use case before it's something brand new. Maybe one of the perls.