There's no way for you or for anyone else to know that it's a dead end.
Also, it's not "simply throwing more compute" - the algorithms have evolved too and they'll continue to.
Also also, it's not "hopefully attain AI results" - we have AI results now and they keep getting better.
People are spending resources on a trajectory which has worked well - we've been cranking up the compute and better results keep coming out, why stop now?