FTDNA was the first company to offer GF testing and analysis, including autosomal, YDNA, MtDNA. It was the go to company when it started in 2000 and for quite some time. To this day it is the best place to go for YDNA and MtDNA testing.
Ancestry did not offer autosomal kits until 2012 and did not become the power house it is today until some years later. People used FTDNA for quite some time. It had more tools for analysis as did GedMatch and the larger data bases at the time.
Now of course Ancestry is the site with the largest data base, and has the fabulous genealogy trees attached to the matches in many cases and the ability for people to make family trees with lots of help and support. They have done very sophisticated norm group research so the ethnic breakdown and historical location of ancestors is amazing. It is the go to site now.
I don't know about the thought process of younger people and LE involvement. Some older people were not so concerned about big brother or LE access back in the day. The figured that if a relative committed a crime then and got nabbed that was fine. But the threat of Big Brother accessing data is more a concern today I think.
Ancestry became huge because genealogists recommended it. Personally, I feel they shot themselves in the foot by not doing Y or mito. I liked 23@me with its oldest interface. (The newer one was horrible and cost its then-owner her own husband and the company, its reputation).
Gedmatch was great and had lots of tools but its owners had to sell it after the whole ruckus caused by GSK and mostly, Paul Holes advertising himself. After that, lots of people pulled their DNAs out of the Gedmatch. Gedmatch as we know it is gone.
FTDNA: I spent a lot of money on but so far, to no avail: my ancestors have no big Y matches. But I’d agree, they are great and have good specialists. But, they do work with LE. To their credit they don’t make a secret out of it.
I think everyone thinks the same: I pay to buy the kits and here is what I get for my money. I don’t pay them for LE or insurance companies to crawl over my DNA for free. Realistically we can’t prevent it but I think most people will stop using the commercial companies tainted by poor protection from either. Young people feel way worse about it, IMO.
Practically nothing is safe, though. However, let us say someone broke into a DNA company and found two close cousins of a criminal and through them, the criminal. Who can then prevent these cousins from suing both the company and LE? The company may say that their DNAs were not “critical” in the process, but: if they know that the cousin has been arrested, they understand that their DNAs and maybe, their trees had to be examined in the process, and it is enough to say: you looked at my DNA without my consent. Not because these cousins care about the criminal. They may be happy that he is caught. But at the same time, they didn’t give their written consent for a 3d party to look at their personal DNAs.
Think of the huge lawsuit against 23@me when the 3d party broke into it. It was a different group, but the issue was about data privacy.