1.) The use of names as a speculative financial instrument (in all shades of grey, up to and including extortion for lapsed or stolen names)
2.) The use of names as vectors of attack, such as by exploiting typos or homographs (such as malicious packages)
3.) The reserving of names you don't have a sincere or immediate intention to use (hoarding/FOMO)
This isn't very much like the situation with domains, which is primarily a result of #1 (there is no market for crates.io names, as far as I'm aware). #3 is a problem to some degree on crates.io, my understanding is that they basically treat this as a human moderation problem. #2 is endemic to all package managers.
By putting a helpful instead of malicious package here, the community (and Richard Dodd in particular) are able to mitigate the hazard of #2 (unless this account is compromised or turns malicious - a better but imperfect situation). If a project called `rg` comes around, they can appeal to moderators to get this name, and probably succeed (as if this were a #3 problem).
This isn't a perfect way to do things by any means, but it seems like a decent balance of concerns to me.
