Google pays Apple a boatload of money to be the main search engine. That said, iOS is a more secure platform than Android, hands down. Google has made some major improvements over the past few iterations of Android but they still have problems with fragmentation and pushing out timely security patches. Exploits happen, whether iOS or Android, but Apple can push out a patch within a day while many Android users have to sit there with a vulnerable device for extended periods of time.
Eh...a lot of this is because Apple feels the need to baby sit it's users far greater than Android. The insecurity of Android largely is because you're permitted to download apps from wherever you choose. Apple is a much more closed eco-system and they don't permit you do have the same level of freedom you get with Android.
Whether that's good or bad is personal opinion. I personally don't need to be babysat with my device.
A house with a steel fence and security guards who turn all visitors away unless they are on the guest list will always be more secure than the house who allows anyone at their door for the homeowner to decide who gets in.
Fragmentation is a huge issue but the misconception is that this falls only in the laps of Google. The carriers shoulder a large portion of the blame here as well. Android O is supposed to assist with the fragmentation issue but this is what comes with an open operating system used by numerous manufacturers.
Mainly, this constant fear of "security" as it relates to us iPhone owners in our defense of iOS is by and large a non-issue for the majority of cell phone users. It's just something that allows us to sleep better at night. The chances of the majority being affected by these things is quite low.