I bought this crossbody bag not knowing for sure whether it would fit my iPad Pro 12.9" (2020 model) with an OtterBox Symmetry Series 360 Case.
Thankfully, it does and, should I buy a Magic Keyboard, it will fit as well. The fit is just right, not too snug, not too loose. So your iPad won't swim in your bag as it would in a messenger bag for 13" or 14" laptops, but it will fit without being hit by the zippers.
The bag is quite well built, stylish, and its safety mechanisms are not a gimmick. I just don't see a pickpocket being able to overcome the main pocket's triple safety measures without you noticing.
Overall, though not advertised as such, it appears to be the perfect crossbody bag for the newer iPad Pro 12.9". I'm very satisfied with my purchase.