Surgeries require having a designated person to look after you. Many injuries require driving to somewhere like an emergency room which can be hard to do if you are the one injured. If you're home with the flu, it's hard to tell when it's bad enough to go to the hospital without another person checking on you. And if you pass out it requires another person to find you like that to get medical aid.

"The 'God Made Trans People' billboard is stupid! God didn't make me! I'm an atheist!" Okay. The billboard sits along a major highway in Kansas. We can deduce that the target audience is not you—it's the centrist evangelical Christians driving along that road who could probably be persuaded to become allies as long as we choose our words carefully and don't make them feel attacked for not already knowing everything about trans rights issues. Another one I see a lot is, "We shouldn't be talking about how right-wing legislation catches [privileged in-group] in the crossfire when [marginalized out-group] suffers far more!" I know. I agree with you. Which is why you and I are not the intended audience of this argument!

The entire point of rhetoric is to win over someone who doesn't already fully agree with you. In this case, let's say that someone is Jennifer, the moderate center-right mom in your neighborhood who doesn't really know or care about transgender issues but would be absolutely horrified by the idea of her teenage daughter having to submit to an invasive inspection of her body just to be allowed to play soccer. Tell her, "Banning trans students from sports will inevitably subject all student athletes to invasive gender-policing," or "Legal restrictions on gender-affirming care will make it harder for you to access the hormone replacement therapy you take to treat menopause symptoms," and she is more likely to question her existing beliefs and listen to the rest of what you have to say than if you lead with leftist talking points that she already has a calcified opinion about or which she thinks do not personally affect her.