I've recently been burning BDXL on Linux using Brasero and a nothing special LG drive. If you can select the burn speed, do not select maximum, I think that is what skunked the first disc I attempted. It will be very slow, and the UI will appear to freeze, but it does burn successfully after several hours.

I've been burning my GOG library slowly in the background and throwing the disks in some jewel cases, and then putting it all in an old ammo can with some desiccant.