If you want a quality user on Farcaster to stick around then you should 100% welcome them by quoting them or tagging them. If you are not doing so then you're significantly increasing their chances of churning. 
Quoting or tagging a user early increases their likelihood of sticking around later. So you better tag em.

Blockchain data analyst. Interested in data science and blockchain.

Analysis-
 https://paragraph.xyz/@yesyes,

https://dune.com/yesyes

does "mentioned/tagged" account for when they are replied to? or only if they are mentioned/tagged within a top level cast?

incentivizing things @ poidh.xyz - come chill /poidh + follow @poidhbot

my hypothesis is same level of retention

people want to have conversations on here! replies to each other are very powerful

This one includes both top level casts and comments. But i should definitely check just for top-level casts, i feel that might have even stronger retention.