Answer

The opposition is in no way connected to halakhic problems. They simply want to preserve the monopoly of the Chief Rabbinate (and of course the Haredim, who receive a free hand from it), because it operates according to their instructions. This opposition arose even before anyone knew what would be included in the reform.
For some of them, it is simply a crude power consideration. Those are wicked people. Another group among them thinks that centralistic control over religious services benefits Judaism. Those are fools.
That does not mean there are no problems with the reform, but there are also problems with the current situation and nobody thinks it should be changed. Therefore the argument is not about problems and not about kashrut. The argument is about power and control. By the way, that is why I support the reforms. Not because they will improve kashrut itself (I tend to think they will, but I have not examined it in depth), but because they will undermine the corrupt and harmful monopoly of the Rabbinate and thereby rescue Judaism from the hands of those who desecrate God’s name and the corrupt people who currently run it.