K repeat advice

We have a 5 year old boy who is turning 6 in June. He is a very anxious child who struggles with change. He has a hard time being away from me (his mom) and gets nervous in many situations. Once he is comfortable he does great and is very out going. He’s very kind, always called “the nicest boy in class” and very well behaved. truly a great kid, but a bit shy and anxious. Also, English is not his first language. He is learning English and doing great but isn’t completely fluent yet.

He currently attends kindergarten in a small private farm school. He LOVES it and loves his teacher so much. This fall he would start first grade in the local public school.

His teacher mentioned the possibility of repeating kindergarten. Mainly to make HIM feel better. One extra year of growing, maturing etc. She thinks it can help his confidence and will make the transition to first grade easier. She thinks summer babies and especially boys often need extra time to mature.

Has anyone here had a child repeat kindergarten and regretted it? Anyone here recommend it?