This has been reported in the past and is still an issue. It was the same in the previous expansion and makes playing the class super frustrating for me as I heavily use macros among all my characters and rely on it for gameplay. This is messed up and makes raiding reliably impossible with key abilities gated behind Apocalypse.
What seems to be happening is a random chance of the macro triggering the spell or the artifact ability from the past. The game does not seem to be able to differentiate between them and will pick one or the other, which makes a macro work or not. Once it is working, it’ll keep working until a game/ui/talent reload is triggered and it’s once again up for grabs which way the game will choose, though mostly the not-working variety.