That is an interesting perspective. I think the importance of Vader’s redemption rests on the father/son dynamic, and I don’t know if a political motivation would have resonated with people on the same level as what we got.
A part of me wishes Vader hadn’t died in ROTJ, and an alternate ST explored a redeemed Anakin and Luke’s dynamic as he earns true redemption.
Kylo was our second chance of this, oh well.