USB Access Point

You have options. Based upon the conversation it sounds as if you have the previous generation of home internet gateway. I would guess if you talk to T-Mobile you could get an upgrade to the newer Nokia gateway which has both 4G LTE and 5G capability. To know if you have 5G available in your area you can use the online verification and find out. Keep in mind the store fronts for the phones currently do not have any knowledge of the home internet gateway and will probably not be able to help you. OK so they know it is there but don't do that part of the business. 

The newer Nokia router with 1.2003.03.0178 software in operation does run the USB port on the back of the router. Will it meet your needs? Maybe The newer router also has 802.11ax WIFI so if you purchase a new shiny PC with an 802.11ax adapter you will be able to leverage it. If you requested the newer router you should expect 3-4 weeks before you might be able to get one given the available inventory and number of requests for these. I got mine back in early January as part of the BETA program and had to wait 3 weeks for it to arrive. I had no solution other than the coffee house. It is something to consider and look into. 

I would prefer to have a local NAS with a gigabit Ethernet connection hard wired vs USB but that is my preference. The bandwidth on the USB interface will be dictated by its version and the link to it via a client through the network. If the wireless connection used is slow well the fastest NAS will be a waste of money. Set your expectations accordingly and do your homework.