Update: Apparently, CNET's report was incorrect, according to T-Mobile's PR and Neville Ray himself. The network is still launching in the first half of the year, but devices that will work with 600MHz spectrum won't be available until the second half of the year. As Ray stated in his Tweet "H2 is just when it gets more meaningful."
T-Mobiles CTO, Neville Ray spoke at Mobile World Congress this morning and stated that the formal rollout of its 5G network won't happen until the second half of the year. The reason behind the delay is actually out of T-Mobile's hands. It is due to the fact that devices with support for its 5G spectrum, won't be available until the second half of the year.
This could be why T-Mobile did not announce anything in regards to the Samsung Galaxy S10 5G, or the LG V50 ThinQ 5G, while its competitors did.
T-Mobile stated at the same event last year, that it would be rolling out its 5G network in the first half of the year. T-Mobile does technically have 5G up and running in a number of markets, so it did keep to its promise. However, it doesn't have any devices available to use on its 5G network, so it has not formally launched the network just yet. The company doesn't want to say "we have 5G" if there's nothing available for customers to use to get the 5G speeds.
Ray did say that he was hoping smartphone makers and chipset makers would have a phone ready that would use T-Mobile's lower 600MHz spectrum. This is what T-Mobile is using for 5G across a large part of the country. However, the first 5G smartphones from Samsung and LG are using high-frequency bands, which are compatible with all of its competitors - AT&T, Sprint and Verizon.
T-Mobile's CTO is still not concerned about AT&T and Verizon pulling ahead in the 5G race, since those two are both using millimeter wave. Which does not cover a lot of area, making it very expensive to rollout, especially in a larger country like the US. Ray said that you can't charge a premium to customers, if the service is only available on a few street corners. That is something we are seeing with internal coverage maps from both AT&T and Verizon right now.
Millimeter Wave or mmWave is not a technology that many carriers are planning to use in the future, it's something that is being used now so they can be "first" with 5G. Past 2020, most carriers will be using higher-spectrum, and ditching mmWave altogether. So Ray does have a point there, stating that his competitors using mmWave is not a big deal for them.
T-Mobile is more focused on rolling out 5G across the nation, and not just covering a few neighborhoods in these large cities. T-Mobile also built its 4G LTE network in a way that it can easily rollout 5G across the country, and has done so already. T-Mobile has touted that it is positioned the best, out of its competitors, for launching 5G service, however, they are the only ones that don't have a 5G device coming to its network anytime soon. It also shows that T-Mobile may not need Sprint as much as they have been saying they do. Of course, that merger is still under review, and it'll be interesting to see what happens if it does go through.