Not really sure if this is true in general. May be true of commercial entities, but I really hope this isn't true in general.
> Furthermore, ceding the technological lead and removing the business incentive likely has defense (read: offense) implications on the global stage.
Does it though? Uncovering faults and cracks of a system does exactly the opposite. Discouraging experts from looking for those faults may give the perception of lead, for a while, but is a dangerous mistake to make in the long run.
Interfering with experts by pulling them out of, say, academia by paying them more and turning them into your PR tools, I think, is detrimental to the advancement of technology. We may be losing a whole generation of scientists to AdTech when they could have been doing more worthwhile work elsewhere(which, by the way, is why we are here in the first place - someone toiled away at a university to come up with a genius idea to design an artificial perceptron).
As to your claim about whether these companies will play a pivotal role in paradigm shifting technology advancements like fundamental research has in the past remains yet to be seen.