The US has a severe brain drain issue in the tech industry. American companies don't pay good salaries for people who specialize in well tested technologies, like the ones you mention from 2015. These same companies prefer to throw tons of money at shiny new things, like blockchain, AI, or whatever the next buzzword will be. Engineers in stablished tech areas will either have to move with the crowd or retire, and never be replaced. New engineers will by necessity have to learn the new shining tech. So the answer is that, yes, we could do these things with 2015 tech, but we cannot because they won't pay experienced people to do this.