Regarding flu vaccines, what I think happened there was this. The flu vaccination is a precaution, so it has to be administered before the outbreak, so obviously it has to be manufactured before it can be distributed and administered, and this was done and cost a lot of money (a political issue).
When the flu actually came around, a lot of people turned out to have immunity to it, especially older people, who are the ones expected to be more vulnerable, so the vaccine proved less necessary than it might have been.
Now I’m no expert, so what I wrote above might be wrong. But at least I know I’m not an expert. I don’t just see a big price tag and scream “conspiracy!”, assuming I know better than all the world’s experts. It takes a special type of intelligence to do that.