"Ragnarok" includes the events of Infinity War? (SPOILERS)

It actually would make sense if Thor died in A4.
Mostly because it would fit with everything that has happened to him so far. Thor has lost everything throughout his journey. The only thing left after Loki, Heimdall and most of his people died was basically for him to avenge what happened. Sure he might have wanted to also help is earth friends... and do his part in trying to save the universe but deep down his biggest motivation was based in "rage, vengeance, anger, loss, regret"... Those we're his own words.

And even though Thor has grown leaps and bounds as a character he still couldn't help himself when it came to his last confrontation with Thanos. Even though in the movie it wasn't totally explicit, the directors did talk/explain and focus a lot on what Thor did by the end of IW and how his vengeful and short-sighted revenge cost everything in the end. As fans we could debate that Thor did his best in that moment but the truth explained by the Russos is that Thor committed a mistake because he wanted to "gloat" that his own revenge was finally served to a dying Thanos. Thor "should have aimed for the head".

A natural progression for the character and his continuous growth would be for Thor to sacrifice the only thing he has left, his life... in order to stop Thanos once and for all correcting his previous mistake and tying up his arc perfectly. Thor said in IW "what more could i lose"... well his life is the only thing left on the table and if he would somehow need to give it away, in order to ensure a successful victory then i'm sure the Thor we know would take that final one for the team.

 

Having said all of that...
I sure hope my favorite avenger doesn't die in IW. It would be a powerful and dramatic loss to the MCU. Thor is now firing on all cylinders and his popularity his greater than ever, it would be a shame to take him out now when his comics are so rich with content and could easily be mined for plenty more adventures with the God of Thunder...

Last but not least. I have no doubt that Galactus will one day be featured in on of these Avengers movies and it would be sad and a massive waste not to have an old, battered but still alive King Thor face against Galactus one last time. If Thor goes down one day i hope he goes down on an all out last effort against the Devourer of Worlds.

Epic stuff.