Sure - if other options are rejected in favour of doing one thing (truly one thing - using one device isn't necessarily one thing, although clearly there are li

Sure - if other options are rejected in favour of doing one thing (truly one thing - using one device isn't necessarily one thing, although clearly there are limits to the range of activities on a single device, but worth noting), then there could be an issue. I'd argue that's relatively rare though - it usually comes down to a lack of better options or a temporary indulgence. Not saying children can't become hyperfocused on one thing, just that parents tend to claim it's the issue when they aren't giving other options or after what isn't really an excessive amount of time with a thing.