I didn't downvote you, but IME Perl is a poor language for embedding. Perl XS is itself pretty bad, whether embedding a C application with Perl, extending a Perl application with C, and especially if you're doing C->Perl->C->Perl mixes--the Perl XS interfaces quickly become leaky abstractions. And don't even get me started on the build process....
I've written far more than my fair share of Perl XS code over the past nearly 15 years. I still use Perl and the last time I wrote Perl XS module was just last month. I could go on for pages about the negative aspects, without having much to say about the positive aspects.
But here's a very concrete reason why nobody should contemplate embedding Perl: I filed this bug report (Thread race in dist/IO/IO.xs) over two years ago:
https://rt.perl.org/Public/Bug/Display.html?id=125685
It's still not fixed. The fix isn't easy, either. It was introduced in an attempt to fix some other stuff. But maybe the biggest reason it hasn't yet been fixed is because the bug is only likely to be encountered when creating multiple Perl interpreter instances in separate threads--a very uncommon usage for Perl.[1] Uncommon usages will not be (and are not) well supported.
Non-threaded Perl embedding may be more common, but ultimately you don't want to be embedding any interpreter that has shared state, especially if the fact of this shared state leaks into interfaces or breaks the interface contracts. Python is also still problematic in terms of not being able to completely erase vestigial assumptions of one interpreter per process. Neither Perl nor Python were originally designed for embedding, and even their extension APIs were bolted on. While they've both been improved over the years and work well for straight-forward C bindings, the fact that neither the languages nor implementations were originally designed for embedding eventually comes through and cause headaches when you want to do anything sophisticated--sometimes even when you're not doing anything sophisticated.
[1] The only significant use of Perl in the open source world that I'm familiar with that embeds Perl this way (multiple instances, multiple threads) is Apache mod_perl. But for other reasons mod_perl creates and initializes all Perl instances from a single thread. This is why the bug went undiscovered for so long after it was introduced, and why there's little impetus to fix it.