One of the craziest examples of intergenerational persistence is from Florence over 600 years.

Table shows top 5 taxpayer surnames today (represented by letters A,B,C,D,E): most of them were high taxpaying names in 1400s (members of key guilds or lawyers)

Likewise, bottom 5 taxpayer surnames today more likely to be in the bottom half of income and wealth more than half a millennium ago.

Florence is interesting because they have (a) tax records from 1400s to today and (b) some very low-frequency surnames.
Link: https://voxeu.org/article/what-s-your-surname-intergenerational-mobility-over-six-centuries

Correction: the bottom taxpayer names today are found in the middle of the taxpayer distribution 600 years ago.

This suggests to me that the poorest people 600 years ago left no descendants today.

You had to be middle class or higher for your surname to survive.

This is another case of survival of the richest