Too late for that, I'm afraid. You have an Android phone and have had Google accounts assigned to it. Google will likely hold onto your data for several months at a minimum so long as you don't sign back in with a Google account, and they even keep "deleted" data for their own internal purposes.
Yup, i know they hold on to it. I think a lot of people think of personal data/info and even privacy as an all or nothing 'privacy is dead so don't bother' sort of thing, that's just not my point of view or how i decide on my settings, services, data, etc, so I try to pay attention to what i can in my data flow, esp as things change, new policies, new advertising/sharing initiatives or if i notice things i don't like and want to change. For example, i specifically asked if anyone knew the data flow of google putting my sisters reviews on my google play store page since i don't have any sort of G+ circle with her, people weren't quite sure, so i changed a bunch of stuff, not knowing which it was, and that fixed it (although i suspect it was only because i turned on the 'don't advertise to me' setting on my phone, although maybe it's cuz i took her out of my contacts, i don't know). Didn't fix it for her, but there are changes she can make to do that. But for me it's not an all or nothing proposition. HP will always know how much ink i use because i let them. Yahoo knows whatever, okay. But for me it's not all or nothing and don't concern myself with data or settings, etc. Some people want their contacts on their sim, and some people like the google contacts and everything else data exchange for services. it's just a preference. So far yes, my contacts are no longer listed as google contacts after i put them as an accessible vcf file, which works better for me than forever having relationship data for google, and every connection i make in the future (esp given they are now treating my contacts like some sort of social media site, that's not what i put them in my phone for). Some people like cross service data exchange, some people like every contact forever data storage used for advertising, some people dont and can avoid it, esp across different services, i just like my stuff separate. I signed up for them separately, and was okay with that. Play store separate from contacts, facebook social sharing stuff separate as well. HP isn't going to send my sister my review of their printer but they know what time i print my documents (and that's pretty much all they know, i mean, IP, that type of stuff too). Now if my first and last name were attached to my youtube, THAT definitely falls under TOO LATE! lol. I do wish they'd stop asking me to merge them, i've rejected it 20x over. What's up with that?
And this was annoying too, i set my contacts not be synced to google, they still of course label them google contacts, even those i never put through google, but okay, get a new contact app, i can ignore it, but there are a few screens related to settings that set your syncing preferences. They look similar, but one you click in and you choose settings, one you click in and it starts the sync. Well, that doesn't make it easy to control my information. I know they didn't do that on purpose, but that's how it is in my phone. I prefer if i don't want to sync i don't have to remember 'which setting screen is this', "oops, press stop!", lol.