It’s quite embarrassing, but I don’t drive very much (have been working from home for almost 5 years now) and let time and miles get away from me. I’m currently waiting to hear back, but I’m very likely going to need to get a new engine, so this will be the most expensive mistake that I’ve ever made.
Not just, "change your oil at the recommended intervals", but "change your oil annually, even if you don't reach the service interval". If you car is going to be sitting for an extended period of time, drain the tank, run the car dry, put the battery on a tender, and change the oil before you start it back up. (Reason: most gas in the US has ethanol in it, and ethanol is hygroscopic. Water in your engine is bad. )