Young people's brains have always been mush, according to the older generation. Your brain is mush according to those older than you. The term for this is juvenoia, and it's as old as humanity.
And yet, when they worried about what television would do to a generation of brains, they were right. The Boomers, as a generation, never became wise, and their brains are mushier than ever.
Regardless of what old people say for young people, which are after all still developing and not so bright or word-wise, there's also actual turning to mush going on. TV, social media, now AI all contributing to further mush-ying.
There's also some specific measurable "turning to mush" going on, like reduced literacy rates, and lowering of IQs (slowing/reversing of the Flynn effect)