As far as I can tell, Postgres is not designed with this inclination towards doing lighter work when clients are waiting and piling up maintenance work to do in background. I think the background work it does is mostly running vacuum on tables now and then.

Contrast that with ClickHouse, for example. It operates in a different niche than Postgres (OLAP instead of OLTP) – with their merge tree engine family [1] that does data deduplication in background.

There is one project of modernizing Postgres' storage engine called OrioleDB [2], but I think the company got acquihired by Supabase [3] and maybe the project has not been progressing very quickly since then.

[1] https://clickhouse.com/docs/engines/table-engines/mergetree-... [2] https://www.orioledb.com/ [3] https://supabase.com/blog/supabase-acquires-oriole