But Perl 6 has the Native Calling Interface which allows you to "Call into dynamic libraries that follow the C calling convention". This means that if you're using XS for accessing external libraries, you won't have to use XS. Which I think a lot of people would see as a plus. For example, this is the code to interface with the C-function ctime:

use NativeCall;
sub the-time(Int() $it = time) {                   # coerce to Int, cu
+rrent time default
    sub ctime(int64 is rw --> Str) is native {*};  # the actual interf
+ace
    my int $time = $it;                            # the rest is synta
+ctic sugar, really.
    ctime($time) };                                # the actual call i
+nto the C-library
}
say the-time;   # Sun Jul 15 17:05:34 2018
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And if you want to interface with your own C-code: turn it into a small library and call that using NativeCall. The t/04-nativecall directory contains several examples of how to do this. All in all, I'd say not having XS is a plus, rather than a minus. As it is XS out there in the wild, that is keeping Perl 5 from advancing in the multi-threaded world. Which is also why Perl 5 ithreads continue to have scalability issues for the past 15 years!