That's because the chances of serious illness with Covid in under 5s is extremely small. Here in the UK nobody under 12 has been vaccinated except those who are extremely vulnerable. The data for England[0] puts the death rate within 28 days of a positive test in the 0-4 age group at 0.8 per 100,000. I believe there are around 3 million children in that age group in the UK so that works out as 24 deaths in that age group in the UK throughout the entire pandemic. Obviously that's a tragic number and awful for the affected families, but at the same time you have to put the risk to your children in perspective for your own sanity.

My kids are 2 and 5 - they've both had Covid at least once, possibly twice and it was indistinguishable from all the other colds they've had since the pandemic hit.

[0] https://coronavirus.data.gov.uk/details/deaths?areaType=nati...