This idea was suggested to me by someone on one of my SE sites (not sure if public linking is desired so not doing that now):
If we have a reputation score (of whatever name) – and I hope we won’t, but that’s being discussed elsewhere – then we should not also tally up a network-wide (instance-wide) reputation score. On SE the number is not meaningful; did you get that score by having 175 accounts, or by answering on high-traffic sites, or by providing a large volume of high-quality content in smaller corners of the network? A number that merely adds up your reputation on all your sites isn’t useful.
Further, if we have reputation, we should allow per-site customization of rep settings – and not having a network-wide total makes this easier. Maybe some sites want question upvotes to be +5, some +10, and some 0. Maybe some sites don’t want to award rep for answer acceptance. Maybe some sites want edits to be worth more than +2. Maybe some sites don’t want to penalize casting downvotes. Maybe some sites want to penalize them more. Sites should be able to customize these values, and doing so makes a network-wide number even more meaningless and confusing.
(This also means that “no reputation” is an implementation of “customize rep values”; a site could set them all to zero. So if we can’t decide to eliminate rep, let’s enable this path to a site doing so.)
One might say that variation within a network is confusing, but: on SE this already happens (StackApps and Area51), and it already happens with SE clones (Physics Overflow looks a lot like SE but has different values), and at Codidact we are emphasizing the idea of a network of communities so I think the idea of different community standards won’t be hard to explain.