Note that "hydrogen" lists among your rather crucial elements necessary for life, and does not feature in Venus' atmosphere in significant quantities.
And, more so, while human life per se requires very small amounts of non-carbon, oxygen, and hydrogen elements, human technology requires very large amounts of non-carbon, oxygen, and hydrogen elements.
AFAIK, sulphuric acid is present in the Venusian atmosphere in large enough quantities to cause obscuring clouds. Though, I imagine that equipment to harvest the hydrogen from those clouds would end up being quite expensive. (Given my limited chemistry knowledge, I'd guess that large amounts of silicon would be involved in their manufacture.) There are also significant amounts of hydrogen sulfide. (Which could be quite a complication for human settlers as well.)
EDIT: FTFA -- "Moreover, while both planets boast ample amounts of volatile life-sustaining materials like hydrogen, carbon and nitrogen, only Venus’s dense atmosphere would be helpful in shielding human colonists from the harsh assault of solar radiation."
And, more so, while human life per se requires very small amounts of non-carbon, oxygen, and hydrogen elements, human technology requires very large amounts of non-carbon, oxygen, and hydrogen elements.