You may not see any salinity barrier to life, but it doesn't seem that your peers agree with you.
I would guess that my "peers" haven't done the reseach I have. To wit:
Industrial bio-oxidation plant with VERY saline environments (water activity well below those quoted in the article), pH swings from ~2 to ~12 on occasion.
The problem?? The bacteria were dying every year along about the late-July to early September time frame, which is kind of inconvenient, because it meant management had to shut down or drastically curtail production at all the OTHER plants down that depended on feeding their wastes to that "biox" plant. Very little was known about the science of the biox process at the time (late 1980's), so management made the decision to establish a research group to find out "why the bugs were dying". I was part of that group.
We established what bacteria were involved (halophiles) and which ones (done by a team of microbiologists--which I am not, but I had access to their data). We also found out why the bugs were dying (but I think giving out that info would be a violation of my secrecy responsibility to the company, even though I no longer work for them). The bottom line is that we found out why the bugs were dying.
And when the cause had been found, and the bugs were no longer dying, the team was disbanded. The only place we "published" was in the company technical reports.
Note that none of this was based on "models"--it was all based on real experimental data generated in laboratory and pilot plant scale reactors, not "inferred" from very limited data.
And, as I said to AndrewC, the wikipedia reference is pretty good at illustrating that bacteria are VERY adaptable, to VERY extreme environments. In particular, some the "black smoker" systems in the deep ocean are at higher salinity and higher acidity than the systems I worked on.
Frankly, Scarlett, I could give a damn whether you are "impressed" or not. I know what the facts are. I have stated them. Believe them or not.