Google cloud console uses over 500 Mb of RAM in the beginning, and after a few actions RAM consumption can grow to over 1 or even 2 Gb. The more actions (creating instances, etc.) you perform, the slower it gets. Therefore it's extremely slow. Using gcloud CLI where possible is the solution. After performing an action, you can copy "Equivalent code" and use it in your CLI next time you need to repeat the action.