Yes, and then they have the correct hormones that are meant for their cells. But even then there have been recorded issues
The evidence with pbs (which seems to have be forgotten about in this debate, but I didn't get to the end) is that the vast majority move onto cross sex hormones.
So the minute you block puberty you have completely medically transitioned a child.
Some of the MPs arguing against may well have been still vehemently believing that it's a pause? Which is also rather thick given all the information that's been circulating post Cass and post Tavistock.