It's a case of choosing how you lose. Android certainly is more open and free in terms of what you can do with it, but you become Google's product and they will mine all meaningful data from your interactions.
What would be swell is an open device you fully control which doesn't spy on you. Turns out that cuts off most of the ways to make big bucks.
You can basically have this today - you might have to give up a few niceties, but if you don't rely on anything too fancy, Lineage + F-Droid, with optional MicroG will generally do the trick for most apps.
Gotta be a bit of tinkerer to set that one up though, not something for grandma.
If she had an iPhone, how many paid apps or in-app purchases was Grandma going to make anyway? Probably none.
Heck, I'm a developer and tech enthusiast that owns numerous Apple devices, and I honestly can't remember the last time I made a financial transaction through the iOS App Store or IAP.
What would be swell is an open device you fully control which doesn't spy on you. Turns out that cuts off most of the ways to make big bucks.