ISPs probably take the cup for worst ratio of technical issues to technical idiots. It's not just a modem, there's a line, an internal network and a really bothersome user all working against optimal service.
Your desire to handle that all in-house by organic, corn-fed, English-as-their-first-language meat-bags is lovely but you'd be bankrupt in a week.
This isn't new. We've had customer service levels for decades. What happened before is you talked to non-technical staff following scripts before escalation. Then that model pushed those staff overseas. Now the lowest rung is a LLM. The trick they have to re-learn when to let the user tell you to step back and fetch a real person. That, and getting the tone of the LLM to not declare everything as if that'll definitely fix the problem.