Looks like the maintainers of xlibre packages in the FreeBSD 15.0 did a great work
I was able to switch from Xorg to XLibre with just two commands and without any issue, lol
https://eugene-andrienko.com/it/2026/01/22/freebsd-15-0-xlibre.html
Worth to mention, that any of my tricks described in the previous blogpost (https://eugene-andrienko.com/it/2025/07/24/x11-configuration-simple.html) are working too without any problems.