When there's a competition this often equates with making customers happy so they will stick with the ISP and perhaps more will switch from competitors.
When there's no competition and customers have no choice who to use it's purely all about squeezing as much money as they can. This means raising prices for the service and reducing cost by paying less to others services even if it would reduce quality of service. The goal is to have service that's good enough to keep people still use them (I mean there is price point and/or quality that people would just not to have service at all).
If a specific action that ISP with monopoly does and it improves quality for customer that's just a coincidence.
That's probably the funniest thing I've read all year
A competent ISP operating in good faith will execute and expand peering agreements when it makes economic sense to do so.