By itself, it's simply an argument that proves too much. Anything you ingest impacts your gut flora. There can be gut microbiome hypos about glyphosate! But you have to actually have them; you can't stop at "it impacts gut flora".
Well, I didn't intend that as a conversation-ender, but it is true. This particular substance inhibits a particular function of certain gut flora that seems important. I think it's safe to call that significant.
What "particular function" is that? If it's "the part that influences neurological function", you don't have a complete argument. If you can't be specific about this, your argument falls apart, because almost everything we eat potentially "inhibits" (or accelerates) different areas of our gut flora.
I'm not trying to make a complete argument, I'm trying to raise a flag. This issue is not well-studied and has very large corporate sponsors who would like to keep selling Roundup-Ready™ crops. One particular measurable function is inhibition of the shikamate pathway in many different bacteria (the majority of the volume of your gut flora is affected).
I understand that this is the realm of crunchy weirdos, but thinking holistically doesn't mean you need to lobotomize yourself.
Here's another paper examining some brain effects of chronic gut inflammation, which could be reasonably inferred as a potential consequence of long-term glyphosate exposure: https://pmc.ncbi.nlm.nih.gov/articles/PMC10661239/
You haven't raised a flag! You've observed (and cited a paper that shows in mouse models under relatively high human dosages) that glyphosate can impact certain gut bacteria species. That's plausible! But all sorts of things do that, and you haven't presented evidence that connects that to an adverse human health outcome. In particular: you haven't cited a source showing glyphosate is causative of gut inflammation.
"It impacts the gut biome" isn't a get-out-of-jail-free card for these arguments; if it were, you could knock down all sorts of things, including specific diets (and most abrupt changes in diet).
Call it (pun intended) a smell test. I have cited a study that shows biomarkers of gut inflammation strongly correlated with glyphosate exposure. Perhaps you should have read it.
I have raised a flag. Lowering your exposure to a novel chemical agent that directly impacts a massive and poorly-understood symbiotic system within the body isn't a bad response. Glyphosate exposure certainly isn't beneficial, so I'll treat it like Pascal's wager: avoiding this has more upside than downside.