They'll be happy to deal with the last mile segment, but anything beyond that is murky and most companies I know aren't going to share much. Helps to have friends on the inside leak some graphs, though.
MRTG graph, ISP circa 1995. Colorized.
See a flat line? that's congestion. Now figure out where it is coming from. Sorry, we have been doing this for thirty years so I'm kind of cranky. It is not a rocket science.
Network congestion issues shouldn't be handed off to field techs to check local loop (last mile) and CPE (Customer Premises Equipment.
I guess I need to remember the ISP I work for here in Australia (front line tech support, and then network operations physical security and infrastructure) was widely recognised as the best ISP in Australia multiple years running, so I shouldn't use it as a baseline expectation.
Yeah, was a good place to work. I was in their Adelaide data centres when iiNet acquired the company.
I’m not sure what the incentives are for an ISP to try to get the provider to fix issues, or even if they would e.g. https://company.chorus.co.nz/what-we-do is notoriously bad for service and the copper network is being deprecated. Locally https://www.enable.net.nz/about-enable/ are doing a good job of service, because they are well subsidised by the government and seem to be effectively operated.
On some days my connection resets 5 times within an hour, which is quite annoying since retraining the connection takes a minute or two. When I call support about it they have zero monitoring in place that would let them know about the recent history of the connection quality, they can only do spot tests of SNR on demand, which of course doesn't show any transient events. According support forum posts of other users they'd have to explicitly enable "long term monitoring" based on user input to get that information.
Of course SNR line quality is an issue separate from congestion, but still, automatic monitoring appears to be limited.
More recent versions of DOCSIS have moved away from that layer of backwards compatibility, so you would probably need some specialised equipment, if it is possible at all (I don't know at what layer exactly encryption happens).