I have used GM EOS and its equiv (look up SLOB) in lots of motors over the years long term. The HDEO oils used to have higher ammounts of ZDDP before they reduced it around the time of the launch of cat converters in big rigs. The thought was too much of the heavy metals could plug the cats up, especially in a motor with oil blow by.
Yes, it's great for cam and engine break-in, but also is helpful for solid lifter and older pushrod, and air cooled motors full time.
Rotella T used to have much more zddp, adding a little of one of the additives brings it back up to the levels of the good old days. But, I use it full time in my tractors, race cars, and air cooled engines, and not in my modern daily drivers, as they don't need it, and because of the cat plugging possibility.