If you have SIBO then you have an overgrowth of the wrong bacteria in your gut, leading to syptoms that often mimic IBS.
My opinion would be that the wrong bacteria can only flourish when they are fed foods that allow them to flourish. And if you check out lists online of foods that do and don’t promote SIBO, then you will find that the ZC/Carnivore foods lists are all beneficial.
Basically, by switching to ZC you will cease feeding the harmful bacteria and they will starve and die off. This may make you feel ‘weird’ for a while, but it passes (literally ). A large percentage of fecal matter is actually dead bacteria.
Worth remembering that any pattern of restricted eating (fasting, vegetarianism, ZC, GF, etc. etc.) will cause some kind of bacterial die off because the bacteria that rely on the absent foods must either adapt or starve. Not necessarily a bad thing, but worth bearing in mind that when/if we re-introduce those foods back again, it may take a while for the bacteria to repopulate. Sometimes they don’t repopulate easily (e.g. after antibiotics), and people choose to take pro-biotics or specific bacteria strains to create a community of beneficial bacteria.