Is there any reason to not use MPO breakout cables to connect servers to the network?

The setup is like this: 10 PowEdge with 2x 10Gbps connected to 3 40Gbps MPO QSFP+ ports on a Dell Switch.

My instinct says this is a bad ideea, but the tech lead keeps pushing this for cost savings. How could I argue against this besides having 1 port config for 4 servers?