+1
From the WCAG standpoint, there were some contrast issues with the old buttons, and it wasn’t easy to find a new color that would have good enough contrast with all the gradient. An example of where the extra constraints brought by the gradient forced a noticeable UI change.
Having flat colors will reduce constraints on colors and increase the range of colors that would ‘look good’ (as in “has enough contrast with the text”).
Do you have a reference for this claim? I’d be interested to read more about this question.
Thank you!