No, these are not automatically off-topic by virtue of using consumer-grade solutions. See What's off-topic; anything in a home setting, or anything that was designed for home use? - MikeyB's answer actually has direct discussion of consumer routers.
But that doesn't make any of your points any less valid.
If it's home use or has a strong odor of home use, it's off-topic.
Any questions with these tags deserves scrutiny! Read between the lines on the question, and if it doesn't have the texture and flavor of a professional environment, then bring that up in comments or simply vote to close.
Looking back in the tags we've certainly got examples that are clearly professional cases - as well as a bad old poll question that should be closed, which has several of our users (including the #6 all time user and a community moderator) stating that they do (or did) use these solutions in the workplace.
Even if it is on topic, if it's clear that the asker is using the wrong tool for the job, telling them so is very much a valid answer - even if it's not the answer they want. I'll most likely upvote it.
