There is no real shortage of toilet paper production, though hoarding is going on at the distribution end, reinforced by media coverage of toilet paper issues.
The president may or may not have the levers to increase supply/production, I defer to other answers there. But perhaps a more relevant response, given that there is no shortage, would be rationing.
However, it's not all that difficult to make the argument that the president, and politicians elsewhere, have bigger fish to fry right now than chasing after a largely inexistent problem.
Also the advent of official, government-led, rationing, on any general goods, in itself would trigger additional worries and panic so it should only be done if there is a real need for it. Informally, supermarkets are already starting to ask customers to limit hoarding-type purchases.