By investing in tech they already know would work, they would vacuum up all the resources and talent around that technology so that nobody else would bother (because who could come in cold and compete against a titan like google?) and then some time later kill all of the projects very publicly in order to make us all think that these technologies were nonviable.
Except instead with every piece of world changing technology they killed, they were buying their future Earths freedom from the apocalypse they were fleeing from, even if that future they were creating destroyed their own and left humanity in a just post-agrarian stage of development.
This group has been infiltrating our timeline for decades, first with blimps, then Atari, then Xerox, now Google.
Their motto is "save us before we destroy us"