i know there are plenty of exceptions to this, but in the one and done era the guys who look like they'll be promising nba players end up largely being one and done. to the extent you are playing against juniors/seniors, yes they may be more physically developed but these also tend to be less skilled players. the good, nba worthy upperclassman still tend to look better than they are, because theyre either much farther along physically than the "good" one and done prospects, or theyre facing other upperclassmen who just arent up to par skill wise