You can easily get far more privacy with Android than iOS, even using a factory, unrooted, rom.

Though I’d say iOS is more private out of the gate than Android.

Once you start installing apps, it’s arguable which is worse - while Apple restricts a lot of stuff, I’ve had apps on iOS that eat battery to pull ads constantly (specifically one Solitaire game, but others too) and lots of Android apps are notorious for wanting every permission and to run at boot. “Free” games on both platforms are notably guilty.

At least with Android you can choose a lot of apps that don’t collect data, and don’t even want a network connection. Unrooted, you can use a VPN full time, that can block network access for apps, or even specific network connections (NoRoot Firewall is one, and ThinkDNS can do this too, IIRC). Like free games - on Android (even unrooted), I can block their network access. And I know it’s effective because it breaks some games.

I’ve used a stock, unrootable phone, and stripped down a lot of stuff using the Universal Android Debloat Utility. It can disable bloatware like all the Facebook components.

Though if OP wants to have a more private and more secure device, I’d go Android with a custom rom, especially Graphene, but Lineage and DivestOS can get you close to Graphene, especially is you manage your layers of privacy and security.