In the FWIW bucket, I decided to experiment with
oil changes on a new car I bought in 1977. I drove a lot more back then than I do now so
oil changes were a regular occurrence and reprensented something I wanted to minimize.
I did some quick math and determined
oil changes and engine rebuilds were in the same ball park for daily driver types like me. I decided to not change oil and just top it off from time to time as needed and see what happened. I drove that car 398,000 miles and never changed the oil or the engine.
On two occasions I had to replace the oil filter because it rusted out (New England winters and road prep). Never smoked and only used a quart of oil every two or three months. The engine was a 385 series 429.
Today's engines are likely more tender and may require more attention to oil changes. All that said Patrick is right about oil and aging. Blackstone Labs will give you more knowledge about what is happening inside your engine than a trip to the parts store for oil.
Ed