This is pure idiocy and ignorance. Or to quote Ramban: אין טעם ואין ריח.
Let me set the record somewhat straight before the resident Appalachian Transcarpathians weigh in.
1) First of all, the OP vastly overestimates the willingness to fund independent Kashrut organizations and the necessary (expensive) infrastructure. Even Tzohar, in addition to its fundraising, depends to a certain degree upon Rav Stav’s position as the Rav of the city of Shoham, affiliated Rabbis’ positions within the Rabbanut and the Rabbanut Kashrus infrastructure. Let me be clear: I am not attacking Rav Stav or Tzohar. Whether the OP and folks here like it or not, Tzohar has become a legit alternative to the Rabbanut and Misrad HaDatot.
2) There is the Rabbanut and there is the Misrad HaDatot. They are two different, albeit connected entities. The Rabbanut is under the Misrad HaDatot. That was how you ended up with the bizarre situation of a minister threatening the tenure of a Chief Rabbi.
3) The Misrad HaDatot is a government ministry that is corrupt and full of Shas and Agudist lackeys. That corruption was how you ended up with the totally preventable situation about 10-15 years ago where the Petach Tikva Beis Din decided (brainlessly) to reject a completely legit conversion done in the USA and thereafter experienced massive blowback from American Orthodox Jewry, from LWMO to Charedim. Rav David Lau warned the court of blowback on both politcal and halachic grounds, but the Shas and Agudist lackeys decided they knew better and got egg on their faces as a result. From the perspective of both an American and an Israeli, it was incredibly embarassing.
The reason why so many Chilonim hate the Rabbanut is because of the Misrad HaDatot, not the Rabbanut in of itself. The Misrad HaDatot dictates – before marriage – who the bride and groom are to learn Hilchos Nidda from. Outside Yishuvim and DL majority areas, they are usually Charedi individuals who should not be teaching Chilonim. Yes, Chilonim are hostile to the idea of learning Hilchos Niddah and they come in with a massive chip on their shoulder, which they should not do. Charedim do not help, considering their inability to reach Chilonim in any meaningful manner.
The only reasonable employees at the Misrad HaDatot are those who are not Charedi. I know this first hand. Upon Aliyah, it was a Charedi clerk who wanted to declare our Ketubah invalid on grounds of “not liking” wording. The wording was the standard American. It was his DL supervisor who first berated the clerk (he recognized my Rav’s name on the marriage certificate), made the clerk call my Rav early in the morning in the USA – while I was in the office, and ask his question. My Rav’s response was, “You call me to verify other Rabbonim. You’re questioning a wedding I performed?”. Even Charedim don’t want to interact with Charedim at the Misrad HaDatot.
4) There is the Rabbanut itself. It is a government office, but its purpose is to maintain a specific level of Orthodox Judaism that is more or less acceptable to all. It intersects with the average Israeli at major points in life such as birth, bris milah, marriage/divorce and death. For the most part it does what it is supposed to do. They try their best, but they are hamstrung by both the secular legal and political system and Charedi politics and policy.
5) Kashrus: The Rabbanut does all the work and is minimally the equivalent of the OU. Charedi hechsherim show up, check one set of lungs (not enough to verify for Kashrus purposes), look at a few ingredients, then leave. The hechsherim are worthless. It’s similar to how the OU does the overwhelming majority of the work in the USA, and the Charedim just piggyback again and do a worthless, cursory check. Charedim might as well rely on the OU and the Rabbanut.
6) If the OP thinks abolishing the Rabbanut will end the things he would like to see disappear, he is blind. Chilonim will just consider it a victory and then try to ban funding to both Charedi and DL Yeshivot and other institutions.