As I've mentioned often, I use Ancestry all the time, not only for my own genealogy, but for researching lots of individuals that I'm not related to. Ancestry is extremely valuable for easily accessing all sorts of basic records -- census rolls, birth and death records, and so on.
The weakness of using Ancestry, though, is in relying on the family trees compiled by other users. Some of them are genuinely useless, and contain data that is clearly incorrect. Nevertheless, it's out there, and can easily lead you astray in your own research.
I came across this example today. It's an entry for a woman who, according to this tree, was born in about 1520. Her father was born in 1537, and her mother in 1525. Her son was born in 1530, when she was ten:
View attachment 226142
There's a lot of this foolishness floating around on Ancestry, so be careful, and look closely at what you import into your own family tree.