I think it depends on the age of the children, I work with 7 year olds (I always abreviate this as "yo" so I don´t know if this is the right way of fully write it - yes, 7 year olds is correct 😁) and I think that the mandatory uniforms make them look equal in each others eyes, so there is not so much diffrence on what they wear to school economically speaking. On the other hand it inhibits some of the particularities that you want to take note of in your teaching ways (correct, but “teaching methods” is more common word), such as the personal preferences of the group, but again I don´t think thats much of a con if you know how to communicate with your students