> Having your own data center is cool

This company sounds more like a hobby interest than a business focused on solving genuine problems.

To me it sounds more like a return to vertical integration.

This is becoming increasingly common as far as I can tell.

There are benefits either direction, and I think that each company needs to evaluate the pros and cons themselves. Emotional pros/cons are something companies need to evaluate as employee morale can make or break a company. If the company is super technical in culture and they gain something intangible that is boosting the bottom line, having a datacenter as a "cool" factor is probably worth it.