... in mice. So if any of this held in humans, I think you'd see reversal of old-age memory problems in people treated with antibiotics that kill Parabacteroides goldsteinii.

As far as I know, no such effect has been observed.

And this article claims inflamation from that strain, the NIH claims otherwise: "Parabacteroides goldsteinii is a next-generation probiotic gut bacterium with significant anti-inflammatory and metabolic benefits, often reduced in obese or diseased states. "