There are 100+ popular extensions around Postgres. They have dependencies on the internal data structures of Postgres. If someone spends the time to rewrite Postgres on Rust and it doesn't support these extensions off the bat, then its DOA.
What I'm saying is that Postgres was built for a long gone age. We need a extensible database written in Rust which can serve as a foundation for any data system. We don't need a relic of the 1980s serving our most critical workloads.
Why does it matter it's from the 80s? You're suggesting people back then were incapable of making good decisions, and people now will make better ones?