Kakarot isn’t Goku’s dead name, it’s not a name he’s leaving behind. It’s Goku non acceptance of the name early on because of his connection to bad things.

He does eventually become proud of the name and embraces entirely of his own will.

The story of the name kakarot is as much Vegetas and his connection and undying pride to his heritage.

As much as it’s Goku’s and his learning to accept what his heritage is, his redefining of it with Vegeta into something good instead of bad.

And the heritage he then goes to leave for his children.

Comparing the story of the name kakarot and what it represents to deadnaming is a pretty wild misunderstanding of what toriyama played out over the years.

Gotta remember this is a story about martial arts written by a Japanese man. Heritage, acceptance and not blaming yourself for the sins of your ancestors are all major themes at play.

Deadnaming while it might on the surface have some cross over. It very much not really at play here in anyway that would be a good faith example.