Bundlers also tie clients to developers without them realizing. I work for a webhost and Many people still assume that if they have access to their hosting then they have their "source code". We see often that people migrate a sites after breaking ties with a developer only to find what they have may function, but is unmaintainable.
Sounds like a contractual thing, not like a bundler thing. The client should always include a clause into the contract that the client must hand all work over after closing the partnership.
Client should ask, but ideally this will be written into the contract beforehand. I don't mind sharing source code but not for re-use in other projects.
Yeah this is no different than receiving a binary rather than the source, bundled code is close enough for this comparison (though it would be probably easier to unbundle code rather than decompile a binary, it’s still a fair amount of work)
You'd struggle to extract a maintainable codebase from a C# or Golang web server after the fact too. As an industry we've been making simple websites on shared hosting for over a generation, clients who ignore the entire world of information about the dangers and pitfalls on this topic are squarely to blame as negligent. It ranks up there with not paying taxes and then acting shocked when the government comes knocking.
While Javascript could potentially be contractually mandated to be written in a way to facilitate production codebase recovery, if you knew enough to ask for that you wouldn't, you'd require them to use your source control and to provide build/deployment scripts instead.
