Both can be true, antibiotics can cause substantial side effects in some people and most people will be fine. Still sucks if you are not one of those most people.
Yes, it still sucks, but so do uncontrolled chronic bacterial infections.
I have never been given a probiotic while getting an antibiotic.
Seems like a good idea. Is that a common thing? Does the evidence support this?
Studies say dunno: https://www.bbc.com/future/article/20190124-is-it-worth-taki...
Personally I try to take some biotic food - yoghurt and the like
As of 15 years ago, according to my doctor, while on the antibiotic, sacchromyces boulardi is the best probiotic to take to try to minimize the risk of adverse consequences.