I tried. It was so great in s1-3 but 4 was so painful I had to force myself to finish.
So 1 question, what reason do they give for Finn's death
They don't give any reasoning at all. He just dies. They leave it to your imagination.
shareI am also watching it for the first time on Netflix, and Season 4 was really weak. It wasn't the graduation of key characters that hurt - the writing was just very weak. Several storylines were poorly written and downright stupid. Why would Marley believe she was gaining weight because her Grease costume was tight, even though EVERY OTHER ARTICLE OF CLOTHING SHE OWNS still fits fine? Why would the other Glee members still stay tight with Kitty after they learned that she bullied Marley into very dangerous bulimia? Why would Finn not tell Will: "Hey, you know, when I kissed your fiancee it wasn't romantic at all, it was just an impulsive way to get her to calm down when she had become hysterical?" Becky bringing a gun to school had no explanation - it just came out of the blue as a dramatic plot device.
I'm not bailing, and thus far (three episodes in), Season 5 seems promising.
They don't say how Finn died, but I believe it was a suicide. Of course, the actor died of a drug OD, but Finn was not using drugs. The way that Kurt said "we shouldn't dwell on how he died, but how he lived" ... that suggests that he died in a way that some people would criticize or judge. If he died of a brain aneurysm, there would be no need to say "let's not dwell on how he died." So I'm taking it to be a suicide or a drunk driving wreck.
Of course, that line was surely meant to refer to Cory Monteith more than Finn. But still, when I speculate as to how he died, I think it was a suicide.