Is there any way to un-spoil an adult cat?

My domestic partner and I have a beautiful, healthy orange tabby who we adore. “Mr. Cheeto” was rescued by my boyfriend about 5 years ago as a kitten and was in the picture before I was. So he really is my boyfriend’s cat.

I love the cat too and do my part to take care of him, buying food, scooping litter, giving him attention, etc. And while I generally enjoy having a pet, there’s one huge problem—my boyfriend has taught his furry friend that bad behavior = reward.

The things this cat does are actually unreal and I’ve never had a cat this badly behaved. His behaviors include chewing through power cords, counter-surfing, not letting us sleep at night because he wants to play or wants ANOTHER can, meowing at the faucet for water constantly, climbing up on high shelves and wine racks and breaking things, aggressive and painful play-biting and too many other offenses to enumerate.

As if this isn’t bad enough, my boyfriend continues to enable him by spoiling and rewarding the bad behavior. If Cheeto behaves badly, he’s sure to immediately get food, or play time, or affection from my boyfriend, and he thinks that I should do the same.

My approach is to withhold these things for 5–10 minutes after the bad behavior because I don’t want to keep giving him the impression that biting or annoying us and destroying our things means he gets a reward. However, I’m coming the conclusion that it’s impossible to undo years of bad cat “parenting” from my indulgent and delusional partner.

Is there anything I can do to discourage this adorable furry terrorist? I know cats are pretty walnut-brained and kind of provocative by nature (part of why we love them I guess) but this one takes it to the extreme. I’ve discussed the option of getting another cat to keep him company but my boyfriend doesn’t like the idea for various reasons. He also shuts me down when I suggest maybe employing a small, gentle spray bottle for certain scenarios where he’s being a danger to himself or others (i.e. knocking down cans of cat food from a very high shelf, walking on my stove etc.)

I’m at my wit’s end and starting to hope this cat is not super long-lived! I hate to say that because he is cute and can be fun but he’s driving me nuts. Help!

(Seriously, I care about the cat and his well-being so please keep that in mind when answering my question.)

Edited to Add: This cat wants for nothing. He’s constantly getting attention (I work from home several days a week), has plenty of toys and playtime etc. He’s just VERY spoiled by my boyfriend.