He says that Windows 10 Pro is actually more efficient in CPU and RAM.

Does Windows 10 use more CPU?

Windows 10 Use Cpu 90% more Than Windows 7.

Does Windows 10 Pro support multiple processors?

Windows 10 supports a maximum of two physical CPUs, but the number of logical processors or cores varies based on the processor architecture. A maximum of 32 cores is supported in 32-bit versions of Windows 8, whereas up to 256 cores are supported in the 64-bit versions.