There’s no “probably” about it. There are hundreds of thousands of doses of tuberculosis treatments that aren’t being delivered and will expire. Every untreated case of TB will lead to some other number of infections and increases the odds of more drug resistant strains popping up. It will take a long time to undo the damage of killing those programs alone.
Even if you subscribe to the notion that US government should not be paying for this, you can phase it out with enough notice for others to step in and take over the funding. The flippant, "tech disruptor" method of abruptly ending an organization that has for decades been funding critical public health initiatives in countries where they would otherwise not happen... That is the truly infuriating part.
In the grander scheme of things, the US voters do indeed have the right to vote for not providing foreign aid. Which is sad of course, but is a valid political position.