Isn't it more impressive that she won as many titles in 8 finals as Venus did in 9? :shrug:
That would only make sense if Serena had only entered 8 Wimbledon tournaments and those were her results every time (being a finalist or winner).
With your logic, in this scenario of Wimbledon results for two players:
Player A: Winner - Lost 1R - Lost 1R - Lost 1R - Lost 1R
Player B: Winner - Runner Up - Runner Up - Runner Up - Runner Up
Player A would be better than player B for having won the title once in 1 Final, whereas player B won the title once in 5 finals.