If you're not getting but 70-100 materials every hour, you're not farming the right spots/taking too long to kill the mobs in the area. I can get a good 150+ easy an hour. I have a chest run on every planet and 3 different runs on Earth. Although I never run chest for more than 30-45 minutes, I still get enough materials for what I need. If I have a free day where I've already done the raid and Nightfall for the week and finished my bounties for the day I might spend the rest of the day farming materials. Then the next day I forget and trade 50 for crucible marks/rep... Like five times lol.