Where the life insurance is provided through a superannuation fund, contributions made to fund insurance premiums are tax deductible for self-employed persons and substantially self-employed persons and employers. However where life insurance is held outside of the superannuation environment, the premiums are generally not tax deductible. For insurance through a superannuation fund, the annual deductible contributions to the superannuation funds are subject to age limits. These limits apply to employers making deductible contributions. They also apply to self-employed persons and substantially self-employed persons. Included in these overall limits are insurance premiums. This means that no additional deductible contributions can be made for the funding of insurance premiums. Insurance premiums can, however, be funded by undeducted contributions. For further information on deductible contributions see "under what conditions can an employer claim a deduction for contributions made on behalf of their employees?" and "what is the definition of substantially self-employed?". The insurance premium paid by the superannuation fund can be claimed by the fund as a deduction to reduce the 15% tax on contributions and earnings. (Ref: ITAA 1936, Section 279).
Many companies separate applicants into four general categories. These categories are preferred best, preferred, standard, and tobacco. Preferred best is reserved only for the healthiest individuals in the general population. This may mean, that the proposed insured has no adverse medical history, is not under medication, and has no family history of early-onset cancer, diabetes, or other conditions. Preferred means that the proposed insured is currently under medication and has a family history of particular illnesses. Most people are in the standard category.
Many institutional insurance purchasers buy insurance through an insurance broker. While on the surface it appears the broker represents the buyer (not the insurance company), and typically counsels the buyer on appropriate coverage and policy limitations, in the vast majority of cases a broker's compensation comes in the form of a commission as a percentage of the insurance premium, creating a conflict of interest in that the broker's financial interest is tilted towards encouraging an insured to purchase more insurance than might be necessary at a higher price. A broker generally holds contracts with many insurers, thereby allowing the broker to "shop" the market for the best rates and coverage possible.
My argument is based on the fact that whole life insurance is often sold as an investment, and therefore many people buy it as an investment. I am well aware that there are other reasons people buy it, and those are explicitly acknowledged in the article. The rest of your questions have already been addressed in both the article and other comments.
All points have merit but, like any service, unprofessional service can be punished by walking. However, point #4, “market blocking” is a particularly confounding practice in P&C (I don’t think this occurs in LIfe & Health). Market blocking is a matter which Insurance Commissioners could easily correct nationwide to the immediate benefit of the customer.