I would wait for the PG19 branching at this point, unless there is a concrete need for backpatching.
This patch fixes just one of the issues I found when trying to have a reproducible PG build... and, given the fact that there are still other issues that make a PG build non-reproducible (see the other patches in https://github.com/monogres/postgres/compare/REL_16_0...monogres/patches/16.0) I'd say it's OK if it's not backported.