One way that collectibles can generate dividends is by renting them out to others. For instance, video game items like CS:GO skins. The popularity of a Chinese skins renting site caused increases in the prices of mid-tier items as investors bought them to lend to others.
Yes, something similar to this actually happened with a giant directory of users. They still could have gone about the rollout much better by adding features that the community requested to slash commands before forcing everyone onto them.
I think that the developer deserves more credit. Being an open source maintainer is difficult and when the maintainer of discord.py initially quit they cited being busy elsewhere in life as part of the decision. I don't think a maintainer should be pressured to work on something just so that the ecosystem is more centralized, although it would have helped to have nominated someone to continue the project instead of archiving it. Open source software has no guarantee of stability and it is largely discord's fault that SDKs must continuously be maintained by the community in this fashion.