Yes, our test does work for that and various hosts-based blockers are supported (like AdAway for Android, for example). In order for our test to give accurate results, the host-based blocker has to add our simulated trackers to its block list, which some lists may not have done yet.
With certain rare configurations (if you have a domain-based blacklist blocker and javascript disabled) this may occur. I suggest turning your js back on just for the test.
That's right, though it's a bit more difficult. Lots of sites use the User-Agent header to determine how to render a page, and may not render it at all if it's an unexpected value. Pages that allow you to install addons to your browsers also use this string to figure out if you're really running the target browser.
"For day-to-day use, the best options are to run tools like Privacy Badger or Disconnect that will block some (but unfortunately not all) of the domains that try to perform fingerprinting, and/or to use a tool like NoScript for Firefox, which greatly reduces the amount of data available to fingerprinters."
TXT isn't an option because the records themselves are unsorted. Use the above command without the pipe to sort looks weird, but not as weird as TXT would.