Sometimes users assume that the top-right time range picker (in Stack Monitoring > Overview) is applied to all data points on the UI.
This is true for Monitoring charts, but not true for most (if not all) Summary values:

Couple of proposed solutions:
Pinging @elastic/kibana-design
Pinging @elastic/stack-monitoring
@igoristic Since you're not using the full filter/query bar alongside the date/time picker. Would it make sense just to remove the global version and piece in that component into the panel containing the charts that the time picker is associated with?

If all Summary Bar metrics across all Stack Monitoring views where the Summary Bar is shown don't use the time picker range, then I think @cchaos's suggestion would work really well. So perhaps we should audit all such metrics first?
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If all Summary Bar metrics across all Stack Monitoring views where the Summary Bar is shown don't use the time picker range, then I think @cchaos's suggestion would work really well. So perhaps we should audit all such metrics first?