Well, your advice to follow my advice is good advice, and I may follow it. But since you included my question "why not just leave him alone," I'll answer it:
The difference for me is that Sundial was an addled old man whose ramblings were mostly harmless and usually not targeted at anyone in particular, whereas I find this other monk in context to be something of a bully, e.g. in his response to the angry ranter this whole fiasco began with. I've never not challenged a bully, meatspace or cyberspace, and I can't say I expect *that* trigger to change. But I will strive to ignore his addled ramblings. Thanks.
The way forward always starts with a minimal test.