In 1930, there was an average of 294k citizens per Rep. In 2020, there was an average of 761k citizens per Rep. At some points in U.S. history, the ratio was 30k:1.
I am not sure whether having very small districts would help or hurt gerrymandering, because it all depends on spatial constraints and spatial/density autocorrelation. I do think it would be good for the Republic if our representatives cam from a local community where you reasonably expect that might have gone to school with them, or have met them at the coffee shop before, and where they can run a campaign by personally knocking on doors, which can be done if the ratio was like 80k:1.