The titanium IS a direct anti-wear/friction replacement for ZDDP (as well as 'dimer/trimer' molybdenum, antimony, boron, etc.).
It can also act as a type of detergent/dispersant (like; calcium, boron, magnesium, etc.) depending on the titanium compound used.
But NO additive will have ANY effect at all on catcon health/life
unless oil is getting past the valve seals/top rings, and getting dumped into, and burned, or partially burned in the combustion chamber.
ZDDP has been shown to be very caustic/corrosive to the engine's components themselves, in the VERY HIGH concentrations (like >2500 ppm) as found in some of the pure race oils (and maybe even ABRASIVE in much higher concentrations than 2500 ppm).
These oils are NOT put into engines where there is any catcon to worry about, AND the oil is changed out at a MAX of 500 mile intervals, or maybe 12-24 hours if used in endurance racing.
These engines are also torn down and rebuilt after every race/event, so the crazy ZDDP levels do not have a chance to do any harm.