Unlike the Mac, the more money you spend on iPads the less value you get in return. The 9th Gen iPad is 5/5 in terms of value but has no fun factor and the 12.9 iPad Pro is 1/5 in value but is extremely enjoyable to use. If you had to guess, how many people are buying the iPad Pros's? It has to be a very small percentage of the total iPad sales, right? Maybe the base iPad and the Air represent 80% of the sales and that's why Apple is reluctant to make iPadOS more "pro" like MacOS.
The last statistics I saw were: over 50% base iPad, around 25% air, less than 20% pro (both models together) and the rest is the mini. That's just units sold, not revenues and even less margins (and this does not even take the even higher margins of accessories into account)
I wouldn't be surprised that, while selling less than half the base iPad, when taking accessories into account, the pro makes as much (or more) profits as the base iPad....
As for value, that's a very subjective metrics, because everyone value features differently.
I would never buy, in 2022, a 3GB RAM iPad, but people have different priorities....(and also different knowledge of the differences between models, some people don't even know specs such as RAM when they buy...)