Having spent a bit of time reading the report and following some of the background material used to formulate the report has been interesting to say the least.
My first observation is that that the political action (drop training) does not totally reflect the report. I suppose that I should not be surprised as the headline is designed to pique interest rather than inform. The key recommendation from my reading of the report is that the authors "do not recommend prioritising the use of resources on unconscious bias or diversity training over alternative interventions which have a more promising evidence base".
The second is that the widely reported conclusion that "training does not work" and can be counter productive. The detail behind this is based on mostly US based studies such as a HBR study and would be better expressed as badly designed training is not effective. Many of the programmes were "defensive" actions to protect the firm from litigation and driven top down as a "box ticking" exercise. It's no wonder these programmes were resisted on the front line and had little or even negative impact.
If you do not really value something, it will be obvious to employees and the programme will almost certainly fail. Leaders will make the wrong decisions as other priorities take precedence, the team will not adapt to do the right thing day-to-day and in the end the desired impact will never appear. Yet another initiative consigned to the history books and the next change will become even harder.
Not only do I believe that diversity matters, but there is robust data to back this up. So working to improve diversity at work is both the right thing to do but also will improve a firm's prospects. This requires actions throughout the firm from how the leaders communicate, how recruitment is managed and how staff are developed. I see that training is a key part of this but it needs well designed training not just box ticking training.
My conclusion: Do things because they are the right thing to do and you believe in it, not just for show. Rubbish training might not cost a lot but it works out to be very expensive in the end when you factor in cash spent and more importantly time that people will never get back in their lives.