I know the state department has recently upgraded rules about what information must be on birth certificates used for primary evidence of citizenship. Certificates issued before the rule changes might not meet the requirements. For someone applying for a passport now, if it has been a few years since they obtained their amended certificate, it might be best to request a new copy to be sure it is up to the latest standards.
I have never heard of birthdate or birthplace allowed to be changed even in an adoption unless it was a correction and documentation was provided to prove the error. If you are a citizen but your birthplace is not in the US, your birth certificate alone can't be used as primary proof of citizenship.
I have not obtained an amended birth certificate after transition yet, however my current birth certificate is one which was amended several years after my birth due to adoption and my full name as well as my parents names were changed. A recently issued copy as well as my old worn out copy does show the original file date (a few days after birth), no amendment date, and nothing on it to indicate that it was ever amended. I know it was and when because I have the court order for the adoption.