This is a shallow treatment of a complicated subject. It doesn't seem to acknowledge that the concept of growth mindset has been challenged, somewhat successfully. [1] It does not seem to have a large effect in the aggregate, according to most meta-analyses. Also, the largest positive effect seems to be for students who are struggling (not surprisingly), which means that perhaps it actually has a net negative effect for students who are not struggling. And there are benefits to praising students for ability when they have unique abilities — this can lead them to feel that they want to cultivate those abilities.
1: https://www.edweek.org/education/opinion-misinterpreting-the...