The machine was indeed targeted at all people, male or female. But this show was in Japan in 1970, and using attractive female models was absolutely the norm (heck, this was even the norm at computer industry trade shows I attended around ~2000; they called them "booth babes"). They would not have had any male models wearing little clothing to show off this machine.
You're right that this part of this history isn't necessarily that important to the machine being discussed in the article, but I think the other poster has a good point that this was absolutely part of the culture of the time, for good or bad, and I don't think this part of history should be ignored personally. Part of reading about something like this is to bring the reader back in time to what it was like being at this show in 1970 and seeing devices like this. Part of the experience was absolutely seeing pretty women modeling things or otherwise being part of the exhibit, because that's something that's completely different these days.
I think it might also be interesting to point out that while having "booth babes" is now out of vogue in the US, it's still the norm here in Japan. Go to an industrial trade show here and it'll be full of men walking around seeing the demos and talking to (generally male) company representatives, while there's a bunch of attractive well-dressed women standing in front handing out brochures and swag and scanning your QR code to put your email address on a mailing list, but who don't actually know anything about the company or products.