am I right in thinking that fermenting unlocks available nutrients and is primarily a fertilizer?
Yes nutrients become more bio-available to plants , similar to fermented food for humans
Are there any other benefits in regard to soil microbes?
yes you add to the soil microbiome , mostly in the way of facultative anaerobes , yeast , fungi , etc etc , it's my understanding they can mostly end up as food for the existing soil life
People in my area are more into aerobic microbe brewing and I'm wondering the pros and cons of fermenting vs microbrewing
in general keeping things aerobic is def a good thing , allot of the negative pathogens we see are anaerobic organisms , brewing a tea with enough oxygen is really important to keep the solution aerobic , when we talk about facultative anaerobes they can switch between living anaerobically or aerobically , you find facultative anaerobes when fermenting , i use EM-1 which are also facultative anaerobes , you can def use both even at the same time , brew a tea & when brewing is complete add EM or facultative anaerobes
Dr Elaine Ingham suggests tea brewing should mostly be used as a foliar spray while compost extracts which aren't brewed should be used as soil drench
the purpose of a tea is to multiply organisms with a food source , there is also a sticky substance that is produced that i can't think of the name of at the min but it's this substance that Dr Ingham suggests is the reason a compost tea is a foliar spray because it will stick to leaves with this substance , so i see tea brewing & fermentation as different things although your still getting plant available nutrients from the compost used & the food added to multiply organisms , both teas & ferments are beneficial imo
if you need organisms you brew a compost tea or make a compost extract , if you need nutrients make or use a ferment but either will give you a bit of both
not sure that's the best explanation but hope it helps