I think people are confusing the term "true random". It's still truly random, but it won't have a uniform distribution over all possible values. For example, a common trick in FPS games is to pick a random spawn point, but exclude spawn points that are too close to other players. Still truly random.
Another trick in RPGs is to increase or decrease the odds of a successful hit according to recent hits and misses, bringing the short-term average much closer to the expected value. It's still "true random", but uses correlation between attacks to create an underdispersed distribution overall. (Basically, you want to make the variance lower to make people happy.)
"Truly random" is usually contrasted with "pseudorandom". In that sense almost all games are not "truly random". But you are right in that "truly random" also doesn't mean "uniform".
Another trick in RPGs is to increase or decrease the odds of a successful hit according to recent hits and misses, bringing the short-term average much closer to the expected value. It's still "true random", but uses correlation between attacks to create an underdispersed distribution overall. (Basically, you want to make the variance lower to make people happy.)