I'd missed that - yeah, one of the features of Snapdragon is that because it started out as a cellphone chipset, the chipset has a radio modem built in. Problem is that OEMs have to pay an extra fee to turn that on and I think a fee for each band activated.
The Surface X had 5G so it's odd they left that out on the 10s.
I generally prefer tablets and laptops with integrated cellular, but in the US it gets even weirder as US cellcos still tend to want tablets and laptops locked to a specific network. Lenovo is particularly bad for this, tending to lock to the most evil cellco - Verizon.
Personally, I've adapted to using my phone as a radio modem either as a hotspot or by just connecting it using a USB cable. It used to be a major hassle but it's gotten MUCH easier (at least on Android - don't use Apple products so can't speak for iOS). Also, my cableco include access to their WiFi network which is widely accessible across my city and for the first time in a long time, having cellular support hasn't been a major issue.