https://www.google.com/search?&q=cognitive+load+site:medium....
Claims about UI/UX regarding 'cognitive load' based solely on conjecture sound like pure pseudoscience. The 'Hollow Icons' article was an egregious example:
https://medium.com/design-ux/a93647e5a44b
If you've accepted the premise that cognitive load theory is going to be a major part of your design/ui decisions, and you're going to invoke it, then I think some meaningful testing is necessary.