(Concern) When is the best time to get orthodontic treatment?

My youngest in 4th grade elementary school has very poor dental alignment.

When I was young, my baby teeth were perfectly tight and cute, but my permanent teeth are large and very crooked, and I can't even speak properly.

When I was in first grade of elementary school, I went to an orthodontic clinic for an examination and consultation, and they said I needed to remove at least four teeth and get braces. They suggested starting with a less difficult early orthodontic treatment from now on.

But the child was crying so much that I have been postponing the correction until now.

The dental clinic our family frequently visits does not do orthodontics. The dentist there says to get braces around sixth grade when all the permanent teeth have come in.

What is the best age to start orthodontic treatment for children?