It's an ecosystem, a market, there is no one single actor to point to.
People couldn't sit on stock for very long because other people were flooding the market as fast as they could.
There was simply scarcity and that's it. State's had their procurement and price enforcement procedures all wrong while they sat idly for the Federal Government to procure for them, it never happened and that is what cost the most time.
The better version of events was that states assumed this level of autonomy at the very beginning and ramped up their own domestic production back in January. They created credits for this kind of production in the private sector, while also subsidizing a retail cost above a certain price, creating a ceiling for consumers. None of this happened and this affected the medical workers and immunocompromised greater than any entrepreneur hoarder could.
Yes but if you do the "obvious" thing of adding a maximum price then not only did you fail to accomplish anything (messing with prices doesn't create more masks out of thin air), you even declared the problem solved so nobody else can attempt a solution!
We live in a market based economy, when the issue spans the continent and world there is no utility in trying to disrupt that market. It is a distraction and misallocation of public resources to attempt to do so.
The "hoarders" were taking just as big of a risk as the people that took the risk to create and sell.
You are missing the point that the necessary stock did not exist. Pointing the finger at people hoarding supplies merely deflects the incompetence to a phantom boogeyman.
That is what the free markets enable, and that is why they are even more important during pandemics and other crises.