My food's selling great, and the lowest I'm going is around 37t per point for plants, with meat at 40, seafood at 60 and insects at 70. A friend of mine is charging more than I am for plants and meat and they're still selling. Are your stacks too big? Are they expiring at weird times of day? Smaller stacks (25ish) sell better and a lot of people snap food up as it expires, so try to list at a time when a lot of people are online. Sometimes a bunch of auctions will expire anyway, but relist and they will go. You don't need to kill your food prices.