Sadly, I think you’re right.
I drive about 25k miles a year, on all sorts of roads, and I see it a lot usually when you see a car or lorry weaving/leaving its lane.
Also in queues of traffic, car behind stops and immediately it’s eyes down by the driver as they’re on the phone.
I was on the A1 a few years ago, in the middle lane overtaking a lorry, when a teabag was ejected from the drivers open window and it landed on my bonnet/windscreen, clearly brewing up.
People seem to do a lot of other things when they should be driving. Phones are some of the first things checked by the police after a serious collision these days, they’ll work out if you were on your phone at that point or during the journey, and the penalty will be much more severe as a result.
It does need a bit of a campaign I think, it must be endemic and people don’t seem to see it as dangerous at all.