That is true for the XC but I don't think it is true for the SC.
The XC has the 8-core Avoton, which is exactly the same as in the 8-core C2 baremetals.
However, the SC has a 2-core Avoton, where the C2 baremetals beginn with at least 4-cores.
Yes, a VPS has shared resources but even the smallest one on Scaleway has a satisfying performance for my use-case.
What I really wanted to know was, are the 2-cores in the SC as fast as the 2-cores of the VC1S VPS on Scaleway?