Javascript is almost always executed in sandboxed, unprivileged environments. The issue here is that this type of obfuscation is easy to add in core os libraries. The JavaScript ecosystem, for all the hate that it gets, makes it super easy to sandbox any running code.

It doesn't matter if it's minified or obfuscated because you basically have to run unknown, untrusted code everywhere while browsing the web with JavaScript turned on. So the ecosystem and tooling is extremely resilient to most forms of malicious attacks no matter how minified or obfuscated the js you're running is. The complete opposite is true for bash and shell scripting in general