A data center or a cloud? It's not difficult to find a good data center to colo at. The problem is then you have to bring your own hardware, technicians, and sysadmins.

However, if you don't trust cloud providers or inference providers for whatever reason then you probably aren't going to be excited to enter a co-op model where you're still effectively renting access to hardware that you don't directly own. There are already reasonably priced options to rent bare metal from a cloud provider.

The only way I see it working is if it's a bunch of medium to large sized businesses getting together to be able to rent out the spare capacity on hardware that they physically control. So an AWS equivalent where each rack is owned by a different company and retail VMs migrate between them transparently. But I question the overall economics of such an arrangement.