Is there any point coaching throw-ins at U7 now?

I would not spend U7 time teaching throw-ins for a matchday problem they do not currently have. Their sideline restart in 3v3 is a pass or dribble in, so I would use those moments to develop things they can apply now: looking before the restart, finding space, receiving and deciding whether to pass or carry. They will have plenty of time to learn throw-ins when that restart becomes relevant. That does not mean a child can never throw a ball in a fun activity. I just would not build a technical throw-in block because “they will need it one day”. At this age, there are far more useful football problems already in front of them than future-proofing every law they will eventually meet.