No? We make sure that pairs of vCPUs (hypertwins) stay together. If you'd like, you can offline your threads in the guest for a fairly similar outcome. Some of us regret that we sell an n1-standard-1 and the shared core machine types, but it's pretty nice to have a $5/month VM price point for those that want it. Most folks doing serious numerical computing end up using much larger VMs, and always crossing NUMA nodes (which is a much larger impact).
Disclosure: I work on Google Cloud (and historically focused solely on Compute Engine).
Disclosure: I work on Google Cloud (and historically focused solely on Compute Engine).