I don’t do much driving day to day and my vehicles live outside in the Chicago area. I aim to change the oil every six months. Sometimes Stuff Happens and I overshoot that a month or two, but it’s always been more often than once a year, except for the year I had a cancer recurrence and six months of chemo. Vehicle maintenance was not at the forefront of my mind, think that was 14 months between oil changes (oops) but the mechanic assured me no harm was done to either my Ford or Toyota by that neglect.
I had a Ford Festiva for over a decade and much hard use. I recently let go my 1999 Ford Ranger. I currently have a 24 year old Toyota sedan. I am far from a perfect auto owner but when I have had to let go of my vehicles - after a decade or two of service - the engines were all in good shape. They weren’t the reason I let go.
Like I said, oil changes every six months (more or less). I use my local mechanic, so in addition to an oil change I can have him look at/address any other concerns or maintenance issues at the same time. It’s not the cheapest method but it’s one that has worked for me.
I tend to drive my newer vehicle more than my older one, a pattern that has held firm over the last 30 years. Nonetheless, I make an effort to drive the least-driven one at least 20 minutes per week. Of course, sometimes a week gets skipped, but as I’ve been told once a month is usually sufficient I figure aiming for once a week with the occasional skip should be just fine. Much of the year I alternate vehicles - drive one one week, drive the other the next week. It’s a slightly different problem than the OP, but the point is that yes, your car needs to be used on a regular even if infrequent basis.
So… from someone who usually keeps their car/pick up 15-20+ years that’s how I keep the engines running.