Even looking at the original BPF which focused on filtering packets as they are forwarded to userspace (think tcpdump)[1] and looking at the extensions that eBPF provides on top to hook into various subsystems[2,3], it's clear that this is going far beyond the use cases originally envisioned. I'd love to see an eBPF paper to follow up / contrast with the '93 USENIX BPF paper.
[1]: https://www.tcpdump.org/papers/bpf-usenix93.pdf
[2]: https://ebpf.io/what-is-ebpf#hook-overview
[3]: http://www.brendangregg.com/BPF/bpf_performance_tools_book.p...