I don't think jitting necessarily precludes counting runtime instructions. You could always jit in an internal variable that gets incremented for each high level instruction being translated. And of course you can optimize the increments within each basic block. There's even a cool minimum spanning tree algorithm due to Larus and Ball originally for path profiling that might be adaptable to reduce increments across the blocks.

I know this is a bit of an aside. The point still stands about the user not wanting their bpf program to terminate at runtime investment.

I get that. Maybe you should read my comment again. Enforcement doesn't have to be dynamic. Any restrictions put on eBPF code could be enforced statically on Wasm code too. Wasm has way better JITs, some of which have been subjected to formal verification. The tech curve for Wasm engines is still pointing up, and eBPF has completely fallen off it and is a liability at this point. It should be abandoned in favor of Wasm.