How about industrialized nations get rid of their agricultural subsidies?

Yes, USA corn subsidies are obscene and often encourage over-use of fertilizers and pesticides. Governments should stop manipulating price signals.

If government was moderately okay at setting prices and production, there would not have been starvation of tens of millions under Mao's rule. If government manipulation of production worked, today North Korea would be the bread basket of the world.

I absolutely can't say whether current subsidies are too high or too low or just at the right level for that purpose, but at least to a certain extent the subsidies and the resultant overproduction are intentional as a safeguard against harvest failures, because you really really don't want to end up with a famine as soon as you get an only even just marginally worse harvest.

It's the same issue we're now running into with renewable electricity production: You either need lots of storage, and for what you cannot store you need to significantly overbuild your production capacity.

Then the price of food goes up, and farmers have a bad time?

Then the rich countries cannot dump their chronic surpluses on the international markets and kill the local markets of developing countries for small-scale farmers.

Oversimplified beyond the point of usefulness. The effects of reducing farmer subsidies are enormous and far more wide reaching than dumping implications in developing countries.

The original question was why can’t we just feed everyone.