That said, I suspect Ancestry.com is much less useful for those living outside the United States. In particular, having ancestors who lived in the country at least 72 years prior to the most recent US Census is what makes Ancestry.com most compelling. That's when census records on individual people become available, as outlined at https://www.census.gov/history/www/genealogy/decennial_censu.... Ancestry.com has done high-resolution scans of all US Census records and parsed them with decently accurate OCR, so you can plug in a (likely deceased) ancestor's name and get their street address, age, occupation, rent/mortgage, those living in the household with them, etc.
I have also not tried their AncestryDNA product, and probably will not. If I were to try direct-to-consumer (DTC) genetic testing, I'd probably use 23andme.
To me, it's just funny. But maybe not to Lutherans?
The practice isn't as cultist as some (gp) may want to imply without understanding what it implies and really means.
You are having some group of people you don't know say something about a dead relative followed by a ritual not based in any science to change which imaginary place they will be in.
It's an interesting loophole to get around a completely sick and twisted part of Christian theology: that many innocents are damned just because they didn't accept Christ and baptism in their lifetimes.
Now, I personally think Christianity is hogwash, and I don't believe in Mormonism. But to be worried that some well-meaning Mormon descendent is going to retroactively make you Mormon after your death is pretty silly. If you don't believe in Mormonism then the proxy baptism is meaningless.