Nope he’s wrong, and a bit worrying he is so risk adverse. He’ll pass that on to make kids anxious if he’s not careful.
She should be using metal cutlery by now.
by 3 my kids were using metal table knives to cut up soft veg like mushrooms when they helped me cook, and stirring stuff on stove with me standing behind holding too
by 4 I’d started to introduce a small sharp kitchen knife to cut softer veg like peppers …by 5 they were managing onions carrots etc
me or their dad were always beside them, and taught them to tuck fingers in and hold food down, and rock the knife.
i only remember 1 of them cutting themselves around 11, and that was small.
They were also using knives to whittle wood etc in beavers under supervision, along with firefighting. By scouts they were expected to be able to manage both knives and fires without immediate supervision.( adults around but not standing over them)
they now, aged twenties, use knives like a pro, and are much faster than me. They even bring their whetstones when visiting and lecture me about risks of not have Uber sharp knives 🤣🤣🤷🏼♀️
they need to learn how to use all blades inc knives, scissors, saws safely from an early age so it becomes habit to use safely. And razors when they get that age. They need to learn to hold adult knives, fork and spoons etc properly asap so they can eat in company and not shovel food in.