Someone’s tzavaah to his children is not the same as saying something is mandatory for anyone else’s children. I am sure that Rov ZT”L had a very strong feeling about this, but that does not put a chiyuv on other people to do as he did.
There were compelling reasons at one time in Jewish history, to not marry a girl with the same name as one’s mother. When entire families lived under the same roof, married children included, there was a fear that a husband might call out for his wife by name in the night, and his daughter-in-law would accidentally respond, thinking it was her husband. This is not really such a likelihood today, though I could see the potential for being accidentally nichshal, in the past.
To me the most practical aspect, is that chalilah if one’s mother were to die, her name could not be used for a future daughter that the son might have, if his own wife had the same name as his mother. This applies to men, as well. At least in the Ashkenazic custom, that is. Sefardim hold differently.
I know several very frum young men in full time learning who married women with the same name as their mothers. Hashem should spare any of them from being in the position of needing a name for their mothers for 120 years, and it should all be good.