The GCP outage [1] in April is a great example. A fire in europe-west9-a "zone" took down the entire europe-west9 "region" (because this entire "region" is actually housed in a single datacenter), which then caused a global GCP console/API outage because GCP's single global control plane couldn't reach europe-west9.
The fact that a zonal issue escalated to a regional and then global outage shows that GCP is not serious about limiting blast radius and all their talk of independent regional/zonal infrastructure is marketing fluff.
In comparison, AWS AZs can be up to 60 miles apart, share no physical infrastructure, and every region hosts its own API/console/control plane.
Also, Nitro. AWS has essentially eliminated the performance overhead of virtualization with Nitro, and years later GCP still has no equivalent so GCP customers still have to pay for that overhead.
1: https://status.cloud.google.com/incidents/dS9ps52MUnxQfyDGPf...