Yeah, let me feed all my internet browsing data directly to google. No thanks.
A local caching Unbound instance is your DNS friend, never Google or Cloudflare or any other large infrastructure company.
If your goal is to maximize the amount of information DNS reveals about your Internet usage, to the maximum number of DNS authority servers, running your own local Unbound instance is definitely a good way to accomplish that.
I just have it set up to forward most zones to my ISP DNS, but you could just as easily do that with 8.8.8.8 or whatever and still minimize the number of requests you make to them. you’ll notice the lower latency too.