Regarding Ancestry and DNA - as a family historian of 20+ years and published a couple of books ....
Ancestry's 'core business' is its subscription database of records that, used with discretion and intelligence is very valuable in tracing your ancestors and their lives. But the golden rule of family history still applies - look at the primary records yourself, not transcriptions. Ancestry is getting more and more primary records on-line. I share a subscription with another researcher and its fantastic for sitting at your desk and being able to make real progress, rather than relying on and waiting for bi-annual trips overseas, which is what I used to do!
I do NOT post my 'tree' on it, as too often people's hard-done research is just harvested by some-one else and used without acknowledgement. Good luck to those that do - I've contacted some of them and gotten some good leads off them, but others again, are just posting some-one else's work.
So "Ancestry is a scam" is a bit of a wild shot.
I haven't done the DNA thing, and won't. If I was just starting out, I
might have done it, but given my innate conservatism, and objection to some multinational company having my DNA 'fingerprints' and my not being able to control what happens to it, its not on. (BTW, in court etc when they say a DNA match is 99.99% .. that's a mathematical match of sample A to sample B. What they don't tell you is the probability that the samples have been tampered with, or swapped, or contaminated!
).
That said, friends of mine have had good matches to unknown cousins etc. You get alerted when another Ancestry DNA subscriber has a match of certain degrees, you can get in touch wit each other or not. So they have advanced their family tree and are pleased with the results.
I don't know anyone who takes any notice of the 'deep' ancestry of regions etc. Its pointless for me to know that ancestors way back came from Iceland, for example, if I don't have a pathway to trace my ancestors there directly.
