These things were still indispensable on my path to being a mathematician though, they just ceased to be relevant as abstraction increased.
On the other hand, if I were to hire you to perform long division I would have complete confidence in you turning in your first calculation within an hour given your research background. So I would definitely say you can do long division.
If software were a purely mechanistic task like long division then I'd have confidence in anyone being able to turn out working code within an hour too. But we can't just keep turning out new programs every time we want to change them. Even with LLMs this is prohibitively expensive. So software is really about being able to build things and maintain them over time which requires a much deeper understanding. Long division is like snakes and ladders. Software is like chess.