I don't think the argument "It's not meant for M1 owners." misses the point at all. It's like when Ford puts a new engine with better tech in one of its models for the new model year. They don't expect everyone with last years car to rush out and get the new one. They are just putting the latest tech in the new model.
People often use the car analogy which makes absolutely no sense. You might as well compare buying an iPad to buying a house then. Its not a comparison that makes any sense. Apple absolutely wants people to upgrade year over year, its easy money for them. They especially want people to use their trade in program as they will turn around and sell your old device for double what they gave you for the trade in.
The M2 isn't that big of an upgrade over the 2018, 2020, or 2021 model. They all use Apple's silicone chips and all are going to have very similar results in real world usage. Yeah the 2022 is going to beat the 2021 and previous models, but its not going to be dramatic like it is comparing intel to silicone in MacBooks simply because Apple was already using silicone in their iPads.
This will be 5 yers now of the same design for the iPad Pro, with no enhancements to the battery, no enhancements to the facetime camera, no enhancements to the speakers, same camera position in portrait. Apple is simply taking the cheap way out here and putting in a new chip into the exact same device as years prior. At least they updated the screen in 2021, but even that was the only meaningful change from 2020 and 2018.