I’ve got an elderly cat that became my responsibility through… circumstances.
He’s a lot of work. He has zero personality or charisma. Worst of all, he harasses me for wet food his whole waking existence. Food motivated is not the word, it’s the only thing he knows, or cares about.
I’m not going to be sad when he dies.
It sounds like tis cat might have had food scarcity issues in the past. Are they overweight? If dry food was left out for grazing would they gorge themselves? Sometimes cats that are extremely food motivated will calm down with food that is always available to them.
Another thing that can help is disassociating you with the food. There are wet food auto feeders, which can help associate the machine with food instead of you, and stop them from harrassing you.
If they are food motivated, and have “no personality” you may have an opportunity to teach them tricks. A good one to start with is shake, because having something like a churu in reach makes then want to paw at it. Say shake, intercept the paw, and then give a lick of the churu. Repeat at the same time daily and you can keep upping the difficulty. This helps you bond with the cat, and you’ll likely see some of the missing personality shine through.