I recently listened to a podcast about 5G (and its supposed health effects) and from what I understand, it will be on the high frequency band of the wireless spectrum, and since high frequency waves have a harder time traveling over distance and objects, cell antennas need to be really close to each other, I think the guy on the podcast said they are almost a block or two apart in NYC. So, from that information and the large footprint of OKC, I imagine OKC may be one of the last major cities to get true 5G like on Verizon. (note- I'm no expert on this subject at all!)

Also, as Swake mentioned, 5G is truly not the same across all the major companies, I watched some speed test on Youtube, guy on Verizon was getting 2 gigabits down, which is twice as fast as Cox's fastest offering and I also watched a guy on Tmobile's "5G" network only getting 60 megabits down, which is basically 4G LTE speed.