This is completely pervasive myth in places like HN.
I founded a startup. For the first three months we hadn't signed a lease for real office space, so there were no monitors, crappy chairs, and old laptops.
Three months later we had all the things.
Productivity did not improve. It absolutely did not double. (It is a bit insane to even claim that it could.)
Those things do not improve productivity in any meaningful way. At worst they are just status symbols. At best they are just signalling. "My company values me and I know that because I have two monitors". Their actual impact on productivity is minimal, despite the thousands of HN posts claiming otherwise.