You raise an excellent point. When you sign up for the US military you give up a lot of your rights. This is definitely bad from a perspective of individual rights, though I can see arguments for a draft being a matter of addressing an existential threat.
Do we as a country feel like COVID is an existential threat? I’m definitely concerned about how we handle future, potentially worse pandemics before we figure out where we draw these lines and what appropriate trade offs are for public health.