Zapping needs to put into the wider context of how Stacker News works.

There are some contributors whose thoughts I value so much that I have turned notifications on for e.g. Justin Shocknet and Kepford.

Interaction and incentives are not immune to zapping but are also not primarily shaped by them.

As long as sites allow users to shape the UX so that bad elements can be filtered out and good elements enhanced, the impact of zaps is not a big deal.