For instance I'm aware of easy piping with | and redirection >

IPC::Run perhaps? From its synopsis:

run \@cat, '<', "in.txt", '>>', "out.txt", '2>>', "err.txt";
run \@cat, '|', \@gzip;
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with less and ls implemented as subs (see also Shell)

Excuse the plug, but I wrote a module that presents a similar interface, but it has more error handling, less problems with shell quoting, and additional capabilities: IPC::Run3::Shell.

There are also several modules I've found very useful in writing shorter code, such as Path::Class and File::Find::Rule.

what are the fundamental obstacles hindering Perl to be used instead of Bash and or PowerShell?

I imagine one issue that might come up is variable scoping, i.e. how long do variables last once they're created - I imagine in a long-running shell, this might end up being a bit of a memory leak.