There is no shortage of STEM graduates. There is a shortage of people actually capable of doing the jobs which, amongst other things, require a STEM background. And for most software development jobs, the latter isn't even the most important qualification.
The STEM shortage is a myth created by people who want to deny that there is a shortage of qualified knowledge workers by equating "qualified" to having a STEM degree.
Nobody actually in the business ever complained about a STEM shortage. We complain about a shortage of competent people.