It's true to some degree but how those needs are fulfilled also matters.
A $300 iPad can do in theory what an $1500 does.
For example, you can do Facetime. But on the $300 iPad, the camera sucks. On the $1500 one it is actually very good.
Both can edit video in LumaFusion. The export time on the M1 will be a lot faster (although the A12 works just fine).
Both can be used for media consumption - but one is far better at this than the other one.
Both can be used to listen to music - but the speakers on the Pro are superior.
And the list goes on and on. It's true that all iPads can fulfill basically the same needs. But there are big differences in the way those needs are fulfilled.
Agreed. It's like buying low end vs high end PCs. Majority of software that runs on high end PCs will also run on low end PCs. However, speed, display, storage, build quality, etc. differs.
The $300 iPad only has 32GB storage. That's very cramped considering half the capacity will be used by System+Other. If I had to use one as my main device, I would be super frustrated. Even 64GB was too small for my use circa 2012 (iPad 3). I constantly had less than 1GB free space on that and I couldn't even update apps without deleting stuff.