If you can afford it, yeah, it's nice insurance against future requirements, or buying a larger monitor in the future. Especially on laptops where it's harder to upgrade later (i.e. typically impossible).
But in the context of the limited budget unfairlane was citing, and the $130 price on that mini pc (which is cheap to the point of being suspiciously cheap, IMO), I see going with 8 GB rather than 16 GB as a perfectly reasonable compromise to keep things within a budget. Per the Steam Hardware Survey, more than 60% of people are still using 1920x1200 or lower. So, if someone asks, "what should I get on a budget?" then my assumption unless they state otherwise is 1080p.
But the price point really does make a difference, and that's part of why I'm glad Firaxis has provided a three-reference-point system, and with multiple CPU and GPU vendors at each tier.