their cultural connection to those homelands was deliberately destroyed by the slavers. if slavery had been ended in one generation then maybe repatriation would've been possible, if they had the means somehow or the government paid for passage.

children of voluntary immigrants lose their connection to their culture nearly as quickly as well, for that matter. There's a discussion James Baldwin had with some white guy i can't find at the moment and he talks about how he can't "go back" to africa any more than the other guy can "go back" to europe.