Probiotics is basically a marketing term, and scientifically meaningless. So: no.

Citation? I see studies testing the impact of various alleged-probiotic bacteria fairly frequently. What am I missing?

I wouldn't go as far as the commenter above but probiotic strains that we can actually produce are an absolutely tiny fraction of the bacteria that can exist in our gut. There's a reason fecal transplants are a thing, and it's not because they're fun for all involved.

without knowing anything, that sounds more dangerous for an infant to me