There’s a couple of answers to that, or maybe they’re all one big answer. If I use Google then chances are I’m using Windows, so all my personal stuff is being handed over to two organizations. It’s difficult, but not impossible to exclude Microsoft and use exclusively Google, thereby handing your data to only one organization. It’s easier to go the Microsoft way if this kind of thing troubles you.
It’s a judgment call on who you trust to better take care of your data. I choose not to trust Google as much as I trust Microsoft. Also, Google relies almost entirely on selling your data or targeting ads using that data so they’re more desperate to get, and keep it. This is evidenced by the fact they give all their stuff away… this gains them enormous inward data flows which they I’m sure eagerly slurp up. MS however has alternative sources of revenue and don’t rely as heavily on using information about you to help themselves.
It is refreshing to use WP without having to deal with Google. My only Google use is YouTube. Separate account, never used it for email, never used it to sign in anywhere else. My exposure to Google is hopefully as low as it could be.
My boyfriend uses Google and I was on his computer recently looking for lingerie. Next day he was complaining about ads for panties and other things on his phone. That’s plain creepy. Imagine if I’d been looking for VD clinics, what would he have thought?
I might respectfully suggest if you want to use Google, get an Android, they’re made for each other, the same way WP is tied to MS’s ecosystem. And things will only polarize more in the future. Getting WP and trying to use Gmail is like complaining you can’t use Internet Explorer on a Mac.