You have to look at aggregates of studies. You can find the one off studies that say crazy shit like 80% of people detransition in the same way you can find actual scientific papers that "prove" climate change isn't real. That's why it's important to look at more than one study and not cherry pick the studies that further ones particular political argument. The study you are referring to has been debunked as having very sketchy methodology and conclusions. The vast majority of studies find the complete opposite of that one study, but fox news will pick that one and ignore the rest, so that people can say "hey, my opinion is backed by research" 🙃

Here's a literature review of 27 "regret"/"detransition" studies that find the detrans rate exceptionally low, because no one has the time to read through 27 separate studies. Lol. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099405/