Mine is year 1 and we already had a few weeks off with sickness, one holiday a few days missed here and there due to weddings and funerals. One of top readers in class, if not no2.
That kind of anecdotal evidence is on a par with someone saying, "I've smoked 40 a day for 60 years and never had cancer". It doesn't prove anything. Indeed, it doesn't even prove that there has been no adverse effect on your child. There is no way of telling how your child would be doing if there had been no absence.
Not sure primary age children missing a few days of school a year is really going to disrupt the whole class.
There are 30 children in a class. Imagine each of them has 5 days off school in term time each year. That would mean that pretty much all the time there would be at least one child catching up on stuff that was covered while they were away. Many teachers hate the disruption caused by children taking term time holidays, although many won't admit it to parents.
as far as I can tell from all the articles and research I have read, the children you are referring to, who often have less than 80% attendance, has not changed
The change in policy came into effect last year. We don't yet have a full year's statistics. However, we do have statistics for the Autumn and Spring terms. These show that, compared with the previous year, overall absence fell from 5.3% to 4.4%. The percentage of pupils classed as persistent absentees fell from 4.9% to 4.1%. The most common cause of absence is illness (or alleged illness). This fell significantly. There has been a dramatic decrease in authorised family holidays and an increase in unauthorised holidays. Overall there has been a 25% reduction in the proportion of sessions missed due to family holidays. The absence rate for children entitled to FSM remains higher than the absence rate for non-FSM pupils. However, both overall absence rate and persistent absences for FSM pupils have fallen and the gap with non-FSM pupils has narrowed.
It is, of course, possible these improvements will not be sustained. But the statistics currently available suggest that the tightening up of policy has had the desired effect.