I don't know, I don't think Mangold will handle Indy the exact same way he did Logan, at least in regards to the character's conclusion.
Some folks have just been burned out by disappointing/underwhelming conclusions to long-running franchises over the years that it's just a default coping mechanism to expect the worst. I understand that point of view. That being said, Mangold has proven to be a really good director so I think some people are really underestimating his talent. I'm still cautiously optimistic for this and will continue to be until the film comes out. Whether it turns out good or bad we have yet to see, but no option is a guarantee yet (except for those who have already made up their mind on hating it, but those peeps aren't worth paying attention to nor having any worthwhile discussion with).