Are you one such person, or is this just an opinion? These other people selected what they wanted to do with their lives. I have, I did, and I appreciate the dedication, training, and experience of professional educators. It is foolish to think that a retiree from another discipline can just be plugged into a teacher slot.
Teaching is not something you decide to take up as a hobby. The reason schools require some course work in education is to get acquainted with the system, understand basic duties, and practice teach to see if you are fit for it. This is aside from the subject matter.
Furthermore, by retreading retired people, paths for employment and advancement of younger teaching professionals may be blocked. For what educational post is a financial executive qualified? an engineer? a product manager? Teaching is an art and a natural gift, not something you just decide to do.
And I'm speaking from experience. It's better that we reframe the context so that dedicated pros do not find themselves in the situation like the protagonist of this article, IMO.
“Are you one such person, or is this just an opinion?”
Yes, I am such a person. I have Masters degree in Economics. And, was employed for 34 years with a large electronics company. During the course of those years I have taught both high school and college. I have found that the attributes you assign are broadly held by those who have spent several years in the private sector. Conversely, those who have spent their careers exclusively in education often lack the broad perspective that those coming from the private sector bring. Lastly, there is a shortage of so called professional teachers that the knowledge and wherewithal to teach the sciences and advanced math courses. This is where private sector talent could contribute greatly. So, suggest being a little more open minded about this. No one is trying to steal your rice bowl. Just want to give back a little, that’s all :)