Of all the things you could level at The Last Jedi (which I love, it's my favourite Star Wars film for a number of reasons) I don't think an absence of bold decisions is a complaint that sticks. If anything, it's proved to be so controversial in the fanbase because it makes so many bold decisions, especially in terms of the decisions it made that will have huge ramifications on the path the next episode takes.
I know Disney will continue to earn the ire of comments across the Internet, but Lucasfilm continues to operate as it did before Disney bought them out, though they actually make movies now! Kathleen Kennedy was producing movies for Lucasfilm from the very beginning and was George Lucas's preferred appointment. It's not a dissimilar situation to the Marvel dynamic. Lucasfilm have more than proved that they are capable of making their own mistakes, though I'm not sure anyone was really in a position to hold Lucas back in the late 90's (see Rick McCallum for details).
I will agree with you to some extent about the other characters and whilst I respect your opinion - Luke, spot on? Never.
If you take the Luke from the Expanded Universe, I'm inclined to agree with you. However, Luke was deliberately ambiguous in
Return of The Jedi and 'the most optimistic man in the universe' was never in that movie. Anyone who thinks he was should watch it again.
He certainly seemed his old self in Timothy Zahn's novels, but I hated those at the time and still do now. Like so much of the expanded universe, it seemed to completely misjudge the spirit of the films.
The most recent trilogy wisely ignores the plethora of computer games and books, which, to some, are
their Star Wars, and that's fine, but they're not the touch point for your general cinema-going audience.
The recent films pick up after
Jedi and they've gone to great lengths to not fill in many gaps in between.
Let's remind ourselves of the Luke we knew and loved.
In a short space of time, he had lost his aunt and uncle, lost his first mentor, found out his dad was the person who killed his mentor, had his hand lopped off by his new found father, loses his second mentor, discovers his crush is his sister and then loses his redeemed father (which he had a pretty big hand in). As I say, optimistic Luke wasn't in Return of The Jedi and I've no reason to think he'd revert to being the whiny farm boy again after burning his dad and partying with the ewoks.
Obviously, it's all open to interpretation, there are no right answers. Considering what I've stated above, and the small snippets of Luke's post Jedi life we see, the Luke in
The Last Jedi is a perfectly acceptable characterisation, if not the one everyone wanted.
If I don't mention it, I'm sure someone will point to the scene where Luke attempted to kill a child in his sleep. But that's not what actually happened. It was a moment of temptation, and we've seen Luke fall into that trap many times in the past. I actually thought that scene was a brilliant way to show how Ben turned without losing sympathy for the character.