I would suggest calling in and asking for customer advocacy group or even filing an FCC complaint but since Cox was just bought things are probably crazy right now in the back rooms of Cox. Like they're not going to care about an FCC complaint when there probably not going to exist in a few months. I don't think you're being throttled. What the technician told you is very likely in common not only at Cox but for the cable internet industry in general. Cable is copper and copper is electrically conductive. Any tear in the sheathing around that copper and it becomes like an antenna. This causes what is called ingress or bad signal leaking into the good signal used by Cox to deliver service over the coaxial. Like hearing noise on a radio station. It can be very hard and time consuming to track the exact source of the problem. You can't stop the signal so you have to find the leak. What speeds do you get exactly? Why do you even you need that speed to begin with? You're not going to see any difference in streaming a video between 50 megabits and 2gbps. Even downloads won't usually saturate a 2 gigabit line because there are not many servers that can handle that speed. To manage that kind of speed to a lot of people is very hard. Only large websites of billion dollar companies can do it and even then if the internet in between them and you is slow, it doesn't matter what they do. So overall, since you're not getting what you pay for and it would be really hard to get them to fix it, I suggest just downgrading since you probably don't even need to be paying that much anyway. Then wait for the company transfer to happen. See how customer support works now. Thank you since it won't be outsourced. See how the new modem that they might give you for free will work any better. You will need your own router, but that's probably a blessing in disguise. If after all the chains you still have issues, then you might want to see if there are any fiber providers in your area. Fiber is much better than cable because fiber uses light which goes over glass or plastic which isn't electrically conductive so physically can't get ingress. It's also faster and better for other reasons too.
Sorry for the bad spelling and grammar. Hurt my back during lawn work so I've been posting more in bed via text to speech over phone. And I can't really even go back and edit because I have cuts of my fingers too. So it's having a hard time registering touch detection accurately. Hope you understood Generally what I was saying though.