Not really, the reason she's there is kinda like the reason people play pantheon (i know, i'm an evil person too). Thing is, while a pantheon does fall off and become useless, she is an adc. she will scale. Teamcomp wise, if you go standard, then it doesn't quite work like you said. However, there are a few ways this could go:
Vayne is an ADC, regardless of what lane she goes. That means that the team no longer needs another ADC bot lane, and they could run Leona/Jarvan to fuck your bot lane up too, without having the lategame teamcomp handicap, and the 2 bot laners will later transition into tanks mid-lategame. Same with top lane, since there are bruisers/tanks bot, there will be no squishy overload even if you run ADC top, and there will be no lack of sustained damage that usually results from running a kill lane bot.
Besides, jungle is another role that can be adjusted to fit the comp, especially since most of the tank junglers now are quite good.