Many countries don't even start schooling for Reception and Year 1 aged children; they start at age 7
Am also from one of these countries. By 7, my nieces and nephews all speak multiple languages, are usually playing an instrument or dancing, and know the basics of reading and writing.
Yes, there's a lot more play, but as a pp pointed out, that's exactly what the benefit it for sending in r and y1 kids. Many MN kids are at home painting rainbows and learning maths through baking, but many of the others I used to see before lockdown are apparently experiencing significant neglect due to parents mentally or financially unable to cope with the disruption to work, routine and family support. While others, even from more privileged families, are being stuck in front of the TV all day without friends, carers or siblings to interact with, while exhausted parents scramble to work.
If the numbers stay so high,then maybe the benefit to staying home is better but it's such an important time for development that I hope it can be done with acceptable levels of safety.