Sci-fi is sci-fi. It doesn't matter when in some made-up history the elements occur. Fact is, I'd still be fighting alien robots if I were getting this expansion.
Except you won't know the context by which they are being portrayed since you won't be picking up this expansion? Being closed minded only denies you the opportunity for some fun. Previously you had said that 85% of all fantasy has sci-fi added to it eventually, so its safe to assume you are only allowing yourself to enjoy 15% of all fantasy genres out there?
And you are basing all this off of one expansion's fluff. What if FFG eventually releases something that indicates that humans were originally from Earth and crash landed their ship on this planet and have been living here for thousands of years, thus making them aliens from another world and establishing that you've been playing sci-fi Runebound from day 1. Is that going to make you sell your sci-fi game completely?
Timescape is not an expansion of the current Talisman, and was a lapse during whatever edition it came out for. Talisman remained a fantasy game after that. More importantly, I simply don't care; I'm not a Talisman player.
It was a lapse? Me and my buds played 2nd edition Talisman with every expansion and didn't bat an eye when we got sent to the Timescape to pick up our chain swords.
And if you don't care, then why bring it up as an example in the first place?