does having a low vision affects to get job in architecture firm?
This facts are supremely dependent on the Architecture Firm and its policies of recruitment. So Low vision may get to a barrier if and only if the firm you want to get recruited at has a policy regarding the eye vision.
In general there are no policies and the skills are highly taken care off. Although some facts like Color blindness are taken seriously purposefully but that doesn't mean that you will not get a job in a firm for being color blind.
So I would recommend you to carry on collecting skills and you will not be left unrecruited.
I hope my answer gives you an insight to the industry. Wish you all the best for your future endeavors!