Parshas Noach

The Meshach Chochma points out that Noach started out as an 'Ish tzadik'- a man a tzadik, but later in his life the Torah describes him as 'Ish hasodeh'- man of the fields. We find the opposite by Moshe Rabbainu. In Parshas Shemos he's refered to as 'Ish Mitzri'- Egyptian man, and at the end of his life the Torah calls him 'Ish huElokim'- a G-dly man. What was the difference between these two biblical personalities? How is it that their lives were polar opposites? The Meshach Chochma answers that Moshe dedicated his life to helping people and bringing them closer to Hashem, thus he was granted extra siatah dishmaiah to grow to a G-dly level. Noach on the other hand let the people of his generation sink to the lowest level without trying to help them and thus he himself fell from the level he was on.
Rashi brings a pshat that had Noach lived in Avraham's generation he wouldn't have been a Tzaddik. This is perplexing, was he a tzadik or not? If yes then he would have been the same tzadik in any generation, why is it relative to other people?
The Massai Hashem explains that Noach believed in Hashem and knew his glory, because he had it passed down to him father to son back to Adam. Avraham grew up in a home of avodah zora, he had no mesora, he came to find Hashem on his own. Had Noach lived in a generation where he wouldn't have had the rich mesora he wouldn't have been a tzadik, for he made no effort to find the creator on his own and would have been just like every other person- devoid of the knowledge of Hashem. That is why Noach couldn't help his generation, it was to dangerous for him to expose himself to the elements and to bring them closer for he didn't possess the tools needed to prove the existence of Hashem.