I think the real benefit here is being able to share structures, etc. with userspace and keep them in sync.

If this was compiling the Golang to BPF then yeah, that would feel ridiculous, but given that it's transpiling instead then, assuming that it's generating correct and reasonable code, I think this is certainly fine enough. Especially if you're just writing a proof of concept or something pretty basic, there's no reason not to start here.

If you're doing something like trying to filter 40Gbps of network traffic in eBPF then you'd probably want to consider something more hand-tuned/low-level, but that might well be a premature optimization for all I know.