Buying a cellular 2021 iPad Pro its own set of perks, including the ability to download iPadOS over 5G if you have an unlimited data plan.
2021 M1 iPad Pro with Cellular Can Download iPadOS Updates Over 5G, No Wi-Fi Required if You have a Huge Data Allowance
Apart from offering a fast internet experience on the go, 5G on iPad Pro has more perks to offer, especially if have an unlimited plan from your carrier. This includes the ability to make FaceTime calls in higher quality and download iPadOS updates using 5G.
Enables higher data-usage features for apps and system tasks. These include higher-quality FaceTime, high-definition content on Apple TV, Apple Music songs and videos, and iPadOS updates over cellular. This setting also allows third-party apps to use more cellular data for enhanced experiences. This is the default setting with some unlimited-data plans, depending on your carrier. This setting uses more cellular data.
What if you have a limited data plan? Don't worry, you can switch this option to Standard or Low Data Mode any time you like from Settings > Cellular Data. Obviously, this change will not allow you to download updates over the air over 5G, hence saving you data.
Keep one thing in mind, if you are connected to 4G LTE, or even 3G, you won't be able to download iPadOS updates using cellular. This feature is strictly limited to 5G. Using anything else will force you to download the update over Wi-Fi.
There you have it, you now have another reason to buy a 5G tablet from Apple.