Threads often have high contact pressures and, when the threaded components have similar hardness or other characteristics, galling can be a significant problem. Anti-seize avoids that problem.
Ti is fairly prone to galling. I figure a specific Ti anti-seize is probably the best choice for a Ti thread, though the difference in hardness compared to Al BB cups probably means this isn’t a major issue. I would be more concerned with SS bolts into Ti.
Copaslip encourages electrolytic corrosion which can be a problem in some circumstances.
Alumslip is generally better than Copaslip when wanting to apply anti-seize to aluminium components.