OP if you read the actual survey and report you'll see that teachers do precisely put it down to the Covid lockdowns and all the measures and screen use which became out of proportion due to them.
It changed behaviour for years to come.
Children starting Reception or those now in nursery, years 1, 2, 3, 4 and most of primary are the babies, toddlers and very young children of exactly that generation.
And you'll remember that life didn't return to normal for a year or two after all the Covid stuff officially was ended. Even now, still, there are people who are testing, wearing face masks and see a running nose as something to be weary of.
People don't hug and kiss that much and socialising behaviour has changed. So much more time is spent indoors. Read the threads about playdates not being a thing, etc. Social workers still often dont come out, working from home etc. Appointments online (which isn't always a bad thing, of course).
Consequences of the three years of the measures will span years and children are the most affected by all.
It also taught parents not to pay for nursery or before/after school and holiday clubs instead plonking the kids in front of the devices.