Because my brother told me about that website after I left the thread. What was I going to do? Go back to it? I said I wouldn't.
Again, even before I left the thread, I conceded that umami may be a word, but no one ever pays attention when I admit I'm wrong lest they have to admit they're wrong about me.
Besides, umami has been in the English language for less than two years.
Because, if anyone can edit it, it's the only way to keep it accurate. AllWords has every word in the English language in its database, as well as a few other languages. If it's a word, it'll be there.