I’d agree it’s a nice read of the character, that he inadvertantly becomes a true Vader-like figure by letting go of his childish obsession with Vader. Wich would play nicely with Palpatine’s manipulating, telling him he can become even greater than Vader. Prompting him to rebuild his mask as he’s earned it.

As for removing the line, the nice thing is this change doesn’t directly contradict canon, it can remain as expanded material such as the Order 66 chip or Boba escaping the Sarlaac. But removing it helps the flow of the story in the movie trilogy. It’s similar to stuff like not having Obi-wan address R2 in the prequels.

Most of the expanded stuff that’s come out only further does a disservice and draws episode IX further apart from VIII. Such as turning Snoke into a ‘test’, removing Kylo’s agency in overturning his Master.