In other words, the only way that Rand Paul can influence the situation in any meaningful way is through political means. So, I find it hard to fault the theatrics with Fauci as distasteful as there are.
I don't buy when politicians start being all like "look I agree with you and that's my end game but first we need to get rid of this guy, and then we win the election, and then we put this other guy in that position and then and then and then". It's not true he can't do better now, it's just not convenient to him and since it's convenient to me I will not support him.
As a member of the legislative branch, Paul's role is fairly narrow: he can summon the people who actually do the work to ask them pointy questions, and try to build support for changing the law. If you look at how things are done in the UK Parliament or other legislative bodies in democracies, it's no different. The question of who is in power is the key one they focus on because they can't micro-manage the details of every possible government agency.
I do think even in this very narrow role he may be succesful. There seems to be sufficient support built-up for an investigation to happen before long, whereas less than a year ago this seemed unfathomable.