Well, but that's part of the problem. When you're trying to appeal to literally EVERYONE, you often end up with a disjointed mess, which is exactly what the Load/Reload project sounds like to many people. Even Outlaw Torn and Bleeding Me were an attempt to appeal to a different type of crowd. Even if it's from the "let's throw in a couple epics to appease the artsy crowd" angle.
I just don't really see this at all. It seems to me like you're starting from the assumption that everything on those albums was just an attempt to please some type of person, and when you start with a claim that broad, literally anything can be evidence for it.
I could just as easily say that
...And Justice for All was just an attempt to please people, and so they wrote To Live is to Die just to please the fans of long instrumentals, and they wrote Dyers Eve to please thrash fans, and they wrote Eye of the Beholder to please fans of mid-tempo chugging riffs, and they wrote One to please MTV (as many thrash fans actually do claim), and so on.
It doesn't make sense to start with the conclusion, especially a conclusion that can't really be disproven, and then make the evidence fit it. I say start with the evidence and see what it proves or suggests. Metallica writing two highly diverse albums on the heels of their big commercial success *could* suggest that they were trying to please a bunch of different types of people... but it could just as easily suggest, as Volante put it, that they had a lot of experiments they were interested in trying, and decided to try them.
I think the motives for the second one make a lot more sense. Why would they be motivated to try to please every different type of music fan? What would be the benefit? They already knew that the key to massive sales was to make a straightforward, commercial-friendly metal album with a couple of ballads mixed in. If they were concerned about pleasing a lot of people, why not just stick to the tactic that had already proven to be a people-pleaser? Who cares if you can add 500 members of the "artsy crowd," if that comes at the expense of time you could spend on another radio hit to add another 50,000 members of the radio hit crowd?