ageism? or wageism?
The real issue may be the wages for these positions are too high in the eyes of corporate america. If you have the skills, or the experience, or the degrees, or the certifications, or one, more, or all of the previous a position requires, then you cost too much. Even the "perfect match" often isn't hired for some lack of soft skills or other "disqualifying factor". Wages happen to rise with age/experience in a field or even overall. When a position requires 5+ years experience and a BS degree, the 20 year veteran is overqualified with or without the degree. The applicant with the right qualifications will have low wage requirements even if lacking other skills or experience.
On occasion evidence of the scam gets out. How does one obtain 5+ years of experience administering windows 2012 active directory based networks in 2015? We can assume we know what was meant was two qualifications of 5+ years network admin and windows 2012. But, the applicant screening checklist is built from the position requirements so nobody actually qualifies.