Diversity document.

I am commenting only on low vision because I have researched that topic
best.

Low Vision
"Visual disabilities range from mild or moderate vision impairments in one
or both eyes ("low vision" or "partial sight"), to substantial and
uncorrectable loss of vision in both eyes ("blindness")."

Unless the WHO has revised its definition since 2010, this statement is
incorrect.  Low vision as a disability is always bilateral.

Relative to barriers.  The statement that most cannot read small print is
correct, but the real barrier is normal print (10pt to 12pt). The best
functional definition of low vision is a person who cannot read normal
print from 40cm (16in) (Legge, Psychophysics of Reading).

Also, low vision ranges from mild to severe. The erratic patterns of visual
damage create situations where a person with mild vision loss cannot read
visually and a person with severe vision loss can (Psychophysics of
Reading) .  Thus, medical definitions are generally of little use when it
comes to barrier removal.

What is generally referred to as mild is considered to be a disability by
the WHO but not by the US.  Moderate and severe are considered disabilities
world wide.