I agree that context matters or the numbers can be misleading. You definitely wouldn't want to conclude much based on one game, for example, for the reasons you gave. Looking at a bigger picture using 6 or 7 games becomes more relevant. As for the last game, the players that played most of the game will have a +/- that is constrained by the final MOV. For the players that played half the game, their numbers are more revealing. Solo was definitely bad and Jaylin was definitely good.
As for Malachi, I am not sure if his play or body language limited his minutes or the other way around but, yes, Silas was clearly playing well so that also impacted Malachi's minutes. I just wouldn't ignore everything that happened before this game. It is pretty clear that the team played really well when Malachi was in those other tough games. Sometimes the reason can't be found in stats or even personal observations. We don't always see everything and we have personal biases. Sure, he may dribble too much or whatever but he has to be doing SOMETHING that greatly helped the team in those games. Help defense? Boxing out so our bigs can get rebounds? Something.