Refer to this thread for details on the planned changes to shared CPU performance that finished rolling out a few hours ago: CPU Quotas Update
In short, reducing your CPU utilization under the ‘baseline’ (by adding more instances, scaling to more vCPUs or reducing the overall workload), or updating the instance type from shared to performance should reduce the steal and throttling percentages. Another option is to leave it running as-is, if your machine is still behaving okay despite the throttling limiting its performance.