I left the default settings from the ./launcher first setup and that was 8 workers.
Same for the db_shared_buffers: 4096MB
However due to some tests, the reason which you can read here, the workers were reduced to 4. It had no effect so I can at least restore them to 8.
The reason it’s not 2xCore is that this is a VM and those are vCPU really, not real cores.
I’ll monitor the instance for a bit and come back to assign the solution if that’s the case, thanks @Stephen