I imagine it can take time to actually validate and build out that new infrastructure at scale after AMD/Intel announces these products to the market. It wouldn't surprise me if hyperscalers like AWS, Google, Microsoft, et. al. get a little bit of early previews of this hardware, but it still takes time to negotiate sales, buy the chips, and then actually receive the new chips and make actually useful systems.

Meanwhile, when AWS announces a new chip its probably something they have already been building out in their datacenters.