PCRE2 is the future of PCRE. The only advantage of GRegex is that
it comes bundled with GLib, which is not an advantage at all.
PCRE2 is widely available, the GRegex abstractions layer are not a
good fit and abstract things that don't need abstracting or that we
could handle better ourselves, there are open bugs (#12997) and
maintenance is spotty at best.
GRegex comes with many of the problems of bundled code, aggravated by
the fact that it completely falls outside of our control.
João Valverde