It really is a great offering, especially when rolled into a family plan. Lots of high quality games on apple TV as well. Only problem is the OS limitation so I can't use a lot of older iPads I have lying around.
I think that would be better covered by a "one time purchase" option. Otherwise, you're asking for either a "starve the dev" category, or something shadier like "show all apps that monetize my location".
No reason not to give the end use the flags for searching. You either get results or you don't. If someone wants to make a simple calculator and not charge for it, they should be allowed to do so and ideally apple will give the tools to the user to find such an app.
Also, devs still do put ads in some purchasable apps So just having a "one time purchase" toggle doesnt solve the problem.
I don't mind IAP necessarily, but it's frustrating when you download an app and then it immediately says you have to pay $10 a month to even open it. Those shouldn't be listed as "free" in the App Store and should be separate from an app that might be "free" but have a minor feature disabled by an IAP.
If the in-app purchase to remove ads is shareable across the family, then that’s fine. If not, I’d prefer to just buy the app and have it share across my kids iPads instead.