Hi and thanks for your replies and taking some time to help with this.
Thanks to your posts and after doing some more digging, this problem with missing ground textures was reported and discussed in 2020 and 2021:
The last couple of posts in that topic, posted in July and August 2021, indicated that the airport, previously missing, had been added to the sim around that time. Then in September 2021, a hand-crafted Suttgart airport was added to MSFS with World Upate 6 (Release Notes (1.19.8.0) World Update VI: Germany, Austria, Switzerland Now Available! - Microsoft Flight Simulator) and there was no further discussion in the topic I’ve linked to above.
So, it would appear that at some point after Asobo/Microsoft chose to add a hand-crafted Stuttgart airport to MSFS that the underlying Bing map textures were again obscured after apparently being made available back around July 2021.
Does anyone have any advice about how to take this forward? Would Zendesk be the correct avenue to ask them to investigate? If I knew how, I would also have this topic integrated into the original I’ve linked above.
As an aside, it is comically non-sensical that the airport is obscured in the Bing maps - if you zoom to Stuttgart airport on Bing maps and then switch on the ‘3D Flyover’ option, the entire airport is shown completely without being obscured at all!