You're correct inpector API is not available in many non-v8 targets. Bun also has somewhat of a partial support for inpector API but at least has a programmable debugger interface. It's not going to be as fast as native inspector but its better than nothing i guess :P
for python sys.monitoring. for JVM, we do bytecode manipulation itself.
bundlers are not an issue because we support sourcemaps. We just need mappings, not code in the sourcemaps and we do sourcemap resolutions out of process so that your app doesnt spend ~200 MB of memory for parsing sourcemaps