This isn't really all that meaningful. In recent years, retailers have been pushing customers to get their holiday purchases in prior to Black Friday, and continue sales afterward, to avoid having to compete with all the other stores offering deep discounts at the same time. As a result, sales are spread out over multiple weeks, and there are fewer purchases on those particular days. "Prime Day" is just an Amazon sale, so they're not competing as much with other stores at the same time, nor are they making it a sale event that spans weeks, so purchases don't get spread out....put up greater sales numbers than what it saw during last year's Black Friday and Cyber Monday combined...
"Christmas in July" sales have been a thing for many years. I would hardly say that one company running a sale counts as a "holiday". It's just a one-day sale by one of the largest Internet retailers.It's kind of amazing (no pun intended) that a single company basically created its own holiday. At least there's no pretense around it, unlike the "greeting card holidays".
Don't worry, I'm sure there are some robots that will be proud to have their jobs. : DAmazon workers in warehouses around the globe went on strike during Prime Day 2019 to protest their working conditions, which have been documented in numerous reports over the last few years.