Unless you buy brand new hardware, hardware is absurdly cheap. Our hardware costs are somewhere around 1/20 of our software costs. It might even be less. I don't see any costs savings on hardware.
What I do see with "microservices" is crossing your fingers that whoever you're buying from knows what they're doing (ie: backups, non-faulty hardware, non-faulty sysadmins, etc.)
The other thing is that you have to rely on Internet access, which, in most of the US, is spotty at best. We're in a major metropolitan, high-tech area, and neither of the ISP's can provide us with reliable service. Hence, all of our software is built to run off-line during our very regular Internet outages. With "microservices", we'd just be stopped from doing any business at all every time the Internet dropped out.