[londons_explore]

This is what you were thinking of:

https://www.justinobeirne.com/google-maps-moat

[gingericha]

Yes, this was the one! Would be interesting to see an update here as it looks like this was from 2017

[ribosometronome]

He did another write up when the data updates started: https://www.justinobeirne.com/new-apple-maps