Excluding anyone for any reason such as disability or race or language s not the wisest course to take. I caution against that attitude. The fact is that in the commerical market place excluding groups of people can put you out of business. Let me give you some figures It is estimated that one out of three people who use the web run with either no graphics, with them turned off, or they cannot see them. It is estimated that one in three people shows some symptoms of dyslexia, making text difficult for them to interpret.
Younger people tend to use the Web for entertainment.
Older people at least in America are using the Web in much larger numbers than was thought originally. Marketwise this is a powerful group to have annoyed at you. If you offer goods and services you must be ADA compliant over the web. The DOJ has ruled on this. If you are an educator your web pages must be compliant.