Neon is indeed unrelated to OreoleDB, but Neon does also provide the separation of storage and compute in Postgres which GP asked about ("Postgres needs options for open-source separation of storage and compute"). A mention of Neon (which is Apache 2 licensed) therefore isn't totally unwarranted.
I understand Neon is open source and I think it’s an awesome product, but apart from the risks associated with longevity of open source once a company gets acquired - although the storage engine is open source, the control plane isn’t and is non-trivial to implement oneself. Orioldedb is positioned as a Postgres extension, which is must easier to setup (even on an existing operating database) than migrating to a completely different architecture that Neon provides.