“I’m genuinly surprised this view of mine is controversial.”
I was surprised that the idea of changing minhagim was so controversial. I imagine you must be from a family with a strong mesorah. I’m not – my parents are both bt, plus we ended up going to a different kind of school than the Yeshiva my father went to. Also, as a girl (and from a family that is mostly female), the whole topic was never particularly relevant to me.
If a family has a very strong mesora, I guess that changing it would be a big deal. But I think that a lot of families don’t. In the OP’s case, since his father gave him permission, and since he is going back to the original minhag of the Ashkenazi world, I really wouldn’t think there would be a problem with it.