a) The article talked about the software not working on Internet Explorer (IE). Older people still use IE. Software Engs with fewer years of experience tend to optimize for FF, Chrome and latest version of IE.
b) The article talked about 'wrong' placement of buttons (probably the software is not responsive or not optimized for phones or older phones)
c) Input fields seem to be rigid (older people will make mistakes)
d) Once you're registered, you can't switch from patient to staff. This should have been designed like a 2-sided marketplace with the ability of one person to sometimes play the 2 roles
If you don't have the right spec/requirements, the output of the engineers will still be bad