ZDDP is not the only known anti-wear agent in existence, apart from the fact that it makes absolutely no difference in normal lubricant operation, people like it because it can be seen in cheap UOA's, manufactures like it because it's just plain cheap. That's the only reason it's still in use, because there are multiple other technologies out there that outperform ZDDP use which don't showup on a $35 UOA.
My tuner, and a lot of other performance LS tuner-builders recommend Brad Penn 10W-40 race oil, which has the same high zinc content of the pre-cat days. If we are all running catted with the rear O2s turned off, catless or with test pipes, what's then concern about damage to the catalytic converter is a moot point, isn't it? Our motors can only benefit from the zinc.