I’m not defending the article as a whole, but he has a point about this: “Religious choice would benefit all. When choice is available, religion in general and Orthodoxy in particular will fare better because people will have the freedom to embrace faith willingly.”
In countries with official religions (like Scandinavia and the UK), in which the government pays the salaries of the religious functionaries, the clerics are lazy and arrogant. Consequently, religious belief and observance tends to go downhill fast, leading to a secularized society that resents or ignores religion.
In contrast, countries like America, with a free market in religion, end up more religious (including more strict religions), because various religious groups have the ability, and an incentive, to attract new followers, and no one feels like they are being forced into anything by the government. Read Thomas Jefferson’s statute of religious freedom — and think about whether you agree with the underlying sentiment.
For demographic reasons, Israel is going to become more Orthodox no matter what. But if the Rabbanut were privatized, it would happen faster, because the chilonim would resent religion far less, and a thousand flowers of kiruv would be allowed to bloom. If privatization helps the heterodox, such an effect would only be temporary.