That's a very bold claim. As a small example let's look at calculators - I remember a lot of claims that having access to calculators would make people's brains atrophy and they'll never be able to do actual math, but what I'm seeing in myself and most people around me is that we're using calculators (and more mathematical software) to tackle significantly more complex problems than people would be able to do if they rejected calculators.
To be clear, I'm not arguing that kids should be using a calculator from the first day of pre-school, but I do absolutely think that using them as later on as augmentation is clearly beneficial.
When you externalise part of your brain in a new tool, like a calculator, that part of your brain is no longer needed and atrophies.