The recommendations tab has been available in the Google Ads interface for a little over a year now, however this has not been a feature within the “modify colums” (table view format) customisation.
Google has conveniently added the optimisation score at a campaign level that allows you to view your performance score (note: performance of how well you use Google automated suggestion rather than performance of your account as a whole)
Warning: Never blindly add Google recommendations. Some of Google’s recommendations work and some do not. It is always best to try/test the recommendations on a campaign by campaign basis. Google’s idea of performance and a human/agency idea of performance can differ greatly.
Optimisation score is an estimate of how well your Google Ads account is set to perform as well as how well your campaigns are set up. Optimisation score runs from 0% to 100%, with 100% meaning that your account can perform at its full potential.