This comes up every year and I always think that most parents who are really anti doing holiday 'work' must have really clever children who don't need to do it as they are top of the class anyway. Well, good for you.
My children are not top of the class. 2 years ago, coming out of Reception and Year 1, they were below the bottom group in their classes. So I did some work with them every day. And yes, I had to force my youngest. Because he'd had a year of being allowed to just play and not bother doing the more focused activities, so he wasn't used to having to do work. I knew Year 1 would expect more work so I had to get him used to it. He got a head teacher's award the first week back as his teacher was so amazed he could now write a sentence.
He didn't have a great Year 1 and started work refusing at school. I changed his school for Year 2 and wanted him to get used to doing work independently. So again in the summer we did work every day. Mostly very easy worksheets that I knew he could do, in order to get him used to working by himself. And all year he has managed to stay more or less in the middle of the class ability wise. I would like him to go into Year 3 ready to work so again will be doing work with him most days just to keep him ticking over.
His older brother is still in the the 'bottom' group of his class. And realistically I know it's unlikely for him to ever get near the top but I would like him to be able to keep up with his group. In Year 1 there used to be work given to the bottom group and then work given to him because he was nowhere near even their level. But now, after lots of summer holiday work for the previous 2 years, he can keep up with the other children in his class who are also not quite at the required level.
So while lots of children might not need to do anything during the summer holidays, if mine don't then I am sending them back to school very much at a disadvantage which I am keen not to do.