They are living, they reproduce. Damaged ones die off.

That's why you're told to take yogurt/other fermented foods after taking antibiotics, to provide a reproductive environment for them to grow.

However it's still a risk you could kill off a whole species and lose their function, so probably best not to take antibiotics unless you really have to.

It's an easy analysis process though, you try to recover for a couple days, if you cannot and no virus is detected, you take antibiotics.

If it's a bacterial infection and it's spreading you have to take antibiotics, otherwise you die and all of your microbes die with you.

The other comments in this thread about the recovery aren’t as optimistic as you are. It seems there is significant damage and it takes quite a long time to recover, if it does.

There's many variables, what kind of antibiotic, their biome before taking the antibiotics, what microbe species were killed and how many were harmed/killed, etc.

There's only a few total comments in this thread overall, I counted 2 anecdotes, not exactly a scientific consensus.

And people are more likely to comment when something goes bad than when something goes good *checks product feedback*