Waldorf education (Steiner school) has been saying this forever. Formal learning does not begin before age 6.
https://en.wikipedia.org/wiki/Waldorf_education#Pre-school_a...
https://en.wikipedia.org/wiki/Waldorf_education#Pre-school_a...
Rather (from Wikipedia):
"Waldorf kindergarten and lower grades generally discourage pupils' use of electronic media such as television and computers.[38] There are a variety of reasons for this: use of these is understood to conflict with young children's developmental needs,[50] media users tend to be physically inactive, and these media often contain inappropriate or undesirable content which may hamper rather than exercise the imagination."