T-Mobile quietly revealed to their customers that they were "putting on-device experience first". Essentially, what this means is that T-Mobile will be prioritizing on-device data instead of Smartphone Mobile HotSpot data.
According to T-Mobile, this prioritization is only applicable once there is a congestion in the network. In such instances, T-Mo says its customers will still be able to use their device as a hotspot. However, the carrier warned that there will be noticeable reduced data speeds when using Smartphone Mobile HotSpot during these network congestion periods.
As explained by T-Mobile, this prioritization is being implemented to ensure that each of their customers continue to get the best mobile experience possible. While there are some expected arguments on whether or not this change is good for customers, it is important to note that on-device data prioritization will only take place once there is network congestion. Hopefully, this is something that does not happen all the time.