I don't doubt that. I even said as much. But one has to understand how to build a web site before they can understand how to build a website for a specific class of individual.
Doing the site first then accessibility second usually either means accessibility simply doesn't get done at all (since people forget and/or priorities change before it is done), or it is retrofitted in a really half-assed way.
This is really important stuff (both legally these days in many countries, but also ethically) so giving it second-billing is probably a mistake.