> What you actually want to compare [..]

The (ex-)scientist in me is looking for a controlled study, ideally published in a peer reviewed journal, looking at - how can I put this - actual data.

60s of Googling gave me this

The effect of a specialized dyslexia font, OpenDyslexic, on reading rate and accuracy https://pmc.ncbi.nlm.nih.gov/articles/PMC5629233/

"A single-subject alternating treatment design was used to investigate the extent to which a specialized dyslexia font, OpenDyslexic, impacted reading rate or accuracy compared to two commonly used fonts when used with elementary students identified as having dyslexia. OpenDyslexic was compared to Arial and Times New Roman in three reading tasks: (a) letter naming, (b) word reading, and (c) nonsense word reading. Data were analyzed through visual analysis and improvement rate difference, a nonparametric measure of nonoverlap for comparing treatments. Results from this alternating treatment experiment show no improvement in reading rate or accuracy for individual students with dyslexia, as well as the group as a whole. While some students commented that the font was “new” or “different”, none of the participants reported preferring to read material presented in that font. These results indicate there may be no benefit for translating print materials to this font."

Advocacy for people with disabilities is important, but actual data may be even more important.