I would say that it's a bad thing because it offends women in the tech industry and makes them feel alienated- the root of this entire story.
It's quite likely that the models in the ads have no objection to what's going on- clearly, they chose to get into the industry. But that's not really the point- there is such a thing as being aware of your environment, and the tech industry has started making real efforts to be more inclusive. If you don't pay attention to this kind of stuff you're going to get a backlash.
Are you saying that they simply made the wrong ad for their tech audience(easier to agree with for a moment) or that they made some huge moral blunder(more difficult to agree with, also the argument by the lady who started the conv).
I think that moral judgements are inherently difficult to make on an objective level, because everyone has different morals. It's why I said that her demanding they take it down wasn't actually a great move- clearly, it offends her, but that doesn't actually give her the right to demand them to take it down.
But imagine, for instance, that she tweeted something similar to @playboy. She'd be very unlikely to get a positive response, or really any support from others. But the tech world is not Playboy, we're supposed to be an inclusive community that wants to encourage more women to be involved.
So I guess my answer is somewhere between your two options- they made a moral blunder in the context of the tech community.