Those are fair points, though I’d argue the Kylo in TLJ embodies the message of “let the past die”. He doesn’t shed his persona, but he clearly takes it in his own path and separates himself from Vader, it’s made clear that him becoming “a new Vader” was Snoke’s ambition, and he ends up killing Snoke and renouncing that path. Learning Rey comes from nowhere further makes him realize his “legacy” didn’t define who he was. So by the end of TLJ it’s pretty clear that living up to Vader’s legacy is as far from Kylo’s goal as possible. He “kills” his past, incuding his obsession with Vader.

That obsession could also explain his percieved “connection” to Vader’s charred helmet. He saw power where there was none, he worshiped the idea of Darth Vader the Sith Lord, while ingnoring the true man that was his grandfather. Much like how our heroes only thought about Luke as the Jedi Master of legend who would solve everything. Both ‘myths’ are deconstructed in TLJ.