It’s not a con, if the data is genuinely safe.
Still, you got one point right; SAFE is better as a name … anything that is a noun works for naming the concept that is “the thing”. Safe is an adjective that requires also Network. Which is why I queried that needs The or A but it’s not better as a noun for needing those.
As above
SAFE is a basic… and by rights it’ll only be the applications that people talk of. Like the machine code on top you put your OS of choice.
Also a brand is easily attacked… an idea, not so much!
Those silly people you suggest will get hostile, likely will be the ones slow to get the idea of what and why it exists anyhow… and to be hoped they will find themselves using it without knowing - or needing to talk about it with a name.
Simply, the future will be that the application they use, is safe or is not safe.
Edit: also, the generic concept of being safe, plays directly into what the product is - so, makes marketing and promotion of the idea, far easier. If you barf random characters into a cold boot of an idea, it is much harder to sell… as with that suggestion of SAIF.