tbf it took 4 years since PG15 support was added for me to fix remote BASE_BACKUP support & wal-g base backups being inconsistent on PG15+ (parameter typo had pg_backup_stop return before wal archived far enough for consistency)
The importance of optimizing (resource) margins and having predictable memory usage increases significantly in the DBaaS/Postgres world, where your process coexists and competes with other critical workloads.
Also, WAL-RUS isn’t rocket science. Postgres already exposes a bunch native constructs for WAL archival, making development fairly straightforward even in Rust.
TL;DR: when to choose Rust or Go really depends on the workload and what you are going after.
That coexistence is also why the GC-free rewrite helps more than the speed numbers suggest. An archiver is allocation-light until it hits a compression burst, then the Go heap can spike toward 2x live right when Postgres wants that memory. GOMEMLIMIT caps the spike but pays in GC CPU during exactly those bursts, so on a small instance, you are trading OOM risk for throughput. Rust removes that dial.