So sad to hear that pp100 does not have much meaning at all ...
it means the same in real life basketball as well. just because PP100 shots is high, doesn't mean individually a high score.
as a team stat, it does tend to indicate things, but more at a team level, which is why is commonly used a team stat for NBA teams.
Personally it is kinda nice to see what happens, because sometimes it shows you that a particular offense was not as good as scoring as what you think it was, or an opposition player really shut down that position. so sometimes its an indicator for things.
with regards to ur question, you will also notice that the opposition SG has average GS and probably poor defense, so from that perspective, his PP100s would be high.