Thanks for the reproducer! I committed a fix onto main. https://git.savannah.gnu.org/cgit/emacs/org-mode.git/commit/?id=58c5c5882
Hi Ihor, do you know anything on the merge progress of your fix into emacs?
I just tested with GNU Emacs 29.4 with --no-init-file and the minimal example still doesn't produce a correct table.
- Jakob