Yes, lesson-planning is time-consuming and overwhelming for a new teacher. It is part of a trial by fire which teachers all pass through on their way to tenure. It helps them fine-tune their knowledge and hone their craft. It weeds out the strong from the weak.
I wouldn't have been inspired to become a teacher if I was robotically handed lesson plans and asked to adapt them to my students. I collect readings and ideas for activities and basically anything my colleagues have hot-off the presses. I don't take whole lesson plans though. We share ideas, but we function independently.
I find the idea put forth by the author of the Chalkbeat piece appalling. It strikes at the heart of why I chose teaching as my profession. I enjoy to exercise my creativity in the service of humanity. I don't want a dedicated "team of qualified people" to hand some lesson to me with all the solemnity of Moses with the Ten Commandments and a pronouncement of "Thou Shalt"--even if it's not one-hundred percent written in stone.
Just as I know other teachers engage with the same topics in different ways with their students, there can never be one superior plan. Millions of minds are always better than one. Nobody should have a copyright on purported educational excellence.