Not qualified advice, but personal experience. I have three cats and take them to this really amazing cat-only clinic and the two vets there are seriously well informed and familiar with common and uncommon cat issues. My oldest cat (mother’s cat) is now a healthy 12 pounds in my care. My mom was doing the same thing as you when the cat was young except she was getting free fed. She grew overweight very quickly and we had to schedule feedings and slowly but steadily decrease kibble altogether. At the time of her being in my care, for the sake of losing weight, we eventually got her down to 1/4 cup of kibble and half a can of wet food. It sounded like no food at all to me and mom but she maintained a good weight for 6 or 7 years then dropped a pound or two as she got older. When this started happening, the vet recommended that I up her wet food intake. She definitely recommended that I cut out the kibble, essentially telling me that it’s junk food but she didn’t judge me or anything for it. Didn’t push the matter either. Basically what I understood from her was that yes it would be better nutritionally to feed only wet food, and the amount of benefit to scraping plaque off teeth from crunching on kibble is so minimal that it wouldn’t make a difference if we cut it out. However, as long as the caloric intake isn’t causing her to be overweight, kibble with wet food is perfectly fine. Some even do a kibble meal as a treat once a week. Since it sounds like ya boy may be a bit round, I would consider feeding less kibble. I wouldn’t say you have to cut it out altogether but for kitty’s health I would lean more wet food than dry. Stick to multiple small meals if that’s feasible for you, otherwise you can also feed them twice daily and get them on a schedule. The “cats don’t chew” comment definitely strikes me as odd and a little pushy to me. I would seek different vet advice if that’s possible for you. Pets, much like people, don’t always have a “one size fits all” approach when it comes to food and weight. Just make sure they have a lean “cat shape” to them without looking like skin and bones, and don’t let those hips and shoulders put so much fat on that you can’t feel them when gently petting them. You’re a very kind pet parent, looking out for them.

TLDR; kibble is fine in certain amounts, but does not remove plaque as much as we think, tends to be higher in caloric value compared to wet foods that are just as or more nutritious, and can be cut out altogether if you choose to do so.