Is it obnoxious for a person to teach introductory French night classes, when fluency will take years and may never be possible for the students given their other commitments?

I think the implication is that it's obnoxious when people equate "learning a little French grammar and vocabulary" with "learning to speak French". Similarly, many of these pop-tech articles don't appear able to differentiate between "learning a little JavaScript grammar and vocabulary" and "learning to program". (I'd bet that the principals at the companies mentioned do know the difference, but they have an obvious incentive not to emphasize it to the press or to their potential customers.)