GA4: Why are my Looker Studio dashboards broken?

Google recently announced it would be enforcing its GA4 API quota limits, so what does this mean in plain English?

Have you seen this warning?

On November 10th, the limit for the quotas of the Looker Studio (and in fact any other connector) using GA4 API came into force. This means that if you have previously built dashboards with multiple widgets connecting to your GA4 API, you may now get an error message…