In my experience, places that filter you out based on that, are places I would not want to work in the first place. There are tons of companies that would kill

In my experience, places that filter you out based on that, are places I would not want to work in the first place. There are tons of companies that would kill for candidates with math background. Aside from that, you may well be getting filtered by the HR department’s recruiter who is just going down a checklist. Smaller companies/start ups are more likely to have actual developers looking at candidates and more likely to be more flexible in requirements.