I have a GM OLM and I don’t like it, never liked the idea, and I ignore mine (except for the annoying light that I need to turn off once in a while). I still just do the 3-5K thing.
GM has one interest and that is selling cars that will reasonably last through a warranty period. OLMs are selling points. Warranty periods are not very long and even very poor maintenance will get many cars through it. I keep cars for a long time - well past warranty periods are up so I tend to follow maintenance schedules that will maximize longevity. GM and their engineers really don’t have my goals or interests in mind.
I can’t say for sure that my engines will do better with more frequent oil changes, but it is really cheap and easy insurance. It is also the case that no one can tell me that my engine will do just as well following the OLM.
Here’s an extra issue that applies in my case and I’m sure in the case of many other drivers. For many people the oil change is the time that other things get checked out (other fluids, tire & suspension checks, leaks, hoses, belts, etc.) This is not necessary & its not the only way things can be checked out but it is a norm. By extending the time & mileage between changes I sometimes wonder how many people end up spending a lot more over time by not finding problems as early as they would otherwise.
To the OP: my advice to anyone who has ever asked is exactly what Goldwing said in the first reply.