¿Las capas de accesibilidad sirven para algo?

Según la tesis de maestría  The Impact of Web Accessibility Overlays on the Usability and User Experience for People with Permanent Visual Impairments, realizada en el marco del Master's Programme in Digital Service Innovation de la Salzburg University of Applied Sciences, parece que las capas de accesibilidad no ayudan, sino todo lo contrario:

The research shows that accessibility overlays, in their current form, do not effectively improve the usability or UX for individuals with permanent visual impairments. Although there is a slight improvement when users are unaware of the overlay’s presence, overall, UX and usability are considered marginal at best and deteriorate upon recognition and interaction with an accessibility overlay. Furthermore, the research displays that accessibility overlays in their current form cannot meet WCAG 2.1 AA standards. The study also finds that users with permanent visual impairments are generally hesitant to engage with accessibility overlays and prefer to rely on their existing access technologies. However, they are willing to use accessibility overlays under improved conditions, which are discussed in the thesis. The empirical knowledge gained guides future technology, designs, policies, and research to create a more inclusive digital world.