Was there not a similar argument made as newspapers became commonplace? Before that the same argument had been made for books but newspapers were on another level - they were effectively limitless drugs, affordable and every single day a new one was available. Instead of talking, laughing and joking with the other workers waiting at the bus stop or in the canteen or whatever, instead you had a sea of silent men reading newspapers.
I’m not convinced phones are without potential harm, but I’m hesitant to get too worked up about them vs. What’s gone before.