This question was closed within just a few minutes of being asked as off-topic due to it being related to home networking. The OP even indicates that the initial intent of the question was related to gaming on his home network, but then specified their current intent (emphasis below is mine):
Also, despite me initially asking this question elsewhere in the hopes of optimizing my home internet connection for competitive online gaming, I am now asking this question purely out of curiosity.
If you continue to read the question, it becomes even clearer that the goal of the question is to determine how fiber or copper transmission mediums impact latency, home networking or the fact that the network isn't in his control isn't even relevant.
Sure, this is a huge topic that could bridge between various specialties (the OP even mentions that this could be related to the Physics stack exchange). However, being that this is NESE, more than physics go into why these mediums are deployed. Physics alone does not comprehensively address the intangibles, such as the practicality and business justifications that drive the decision of which medium to deploy.
This is an FANTASTIC question about an area of networking that isn't often addressed for newer engineers or someone like OP who is simply curious. I'd argue even the more senior level engineers who may choose to buy fiber over copper may not even understand why beyond cost or bandwidth, the sort of details that this question yields is the sort of thing that makes engineers great.
Having standards for how questions are asked or what is on topic is necessary. As is evident on this site, networking touches a ton of domains and much of that interdomain overlap is very much off-topic. However for cases like this, where the OP supplied the necessary context and plenty of effort, do we really need to expect perfection to be the bar for entry to this site? We have a banner when new members ask questions that basically says "be nice", but we're treating them as if they have to walk on egg shells to participate.
I can think of about 10 different ways that we could have adhered to the set rules and answer the OPs question.