Closed source eBPF code is somewhat similar to a closed source kernel module, just one that doesn't need to be recompiled for every kernel version and cpu architecture. Good luck figuring out what it's going to be doing.
eBPF is a very restrictive format. It's closer to .NET bytecode (trivial to decompile) than native machine code and the verifier sets strict limits to prevent things like unbounded loops. That makes any obfuscation a lot weaker.