@moud:
you hype up an opponent for way too long just to replace him with a newly introduced conflict,
When you entirely eliminate absolutely all context whatsoever sure they can be roughly compared. But then you haven't actually said anything whatsoever now have you.
Also you phrase this as if Mihawk is thrown away. Like everything was a waste of time. Except no not really. Developing him more and more into a positive character close to Shanks and even Zoro makes his loss felt. Even the relationship itself serving the purpose of lighting an ever more intense fire under Zoro's ass to get better throughout the series. Inadvertently even without mentioning the two year training period…Mihawk fits the bill as Zoro's mentor/idol figure in the same way as Shanks to Luffy. Both older guys existing as the peak in the distance that keeps Luffy and Zoro running forward. They're the inspiration or at least a very core one that shares space with Kuina and others. This is what's really important about the Mihawk character, not the eventual fight if it even gets to happened or not.
And none of that is wasted at all by Mihawk and Zoro never getting to have another last duel.
like I said zoro has never interacted with shyrio it doesn't matter how hyped up his crewmates are if there's no conflict being built up (take luffy/BB relationship for example)
The Luffy/Blackbeard relationship is really not all that developed yet. Certainly not to the level needed for Blackbeard to be the final foe. Currently Luffy has a sort of cartoonish "Grr I don't like that guy!" feeling toward him. FAAAR short of where it will eventually need to be. So really no. Blackbeard has been built up in the One Piece world and narrative for us the readers. But the relationship with Luffy is very thin at this moment. Obviously this will change. Big time.
You put far too much premium on time as meaning something as well. It really doesn't. One arc involving Shiryu centrally is all Oda needs to elevate him to a memorable threat that the Strawhats (Zoro specifically) are concerned about. Mihawk didn't even have that, he had an extremely memorable half dozen or so chapters within an otherwise unrelated arc. And that was all it took for people to get excited about him and invested in Zoro's dream. Good storytelling works that way.
You're also looking at things too individually. The Blackbeard Crew as a whole is an entity that collectively looms over the series and Strawhats to some degree. Each one of them benefits from that collective threat even while not yet being individually developed. Shiryu doesn't exist in a vacuum. Heck neither does Mihawk.
now i'm not saying the fight won't happen cause it obviously will only that it won't be zoro's last fight
So you don't think the Blackbeard crew are the final villains? That's a mistake to make.
.. and mihawk was set up as a good guy from the beginning i don't think him being more "friendly" with zoro would stop them from having a great duel i'm sure it wouldn't be a first
It inherently has extremely fewer stakes attached to it. This is inarguable. There wouldn't be a greater goal attached to it as Mihawk doesn't need to be stopped from doing anything, in fact it would be counter-productive the more aware of common enemies the Shanks clic and Strawhat crew are. Nor is there a sense of emotional intensity to it, of hate or revenge or anything. Honorable knightly respect between peers who are solely out for physical competition is cool and all but it makes for poor drama in a series like One Piece (you'd have to be playing things much more realistically and seriously like Vagabond). And of course there really isn't a sense of risk to it at the end of the day, no matter what they might say about possibly killing the other one it just straight up doesn't measure to an actual bout of mortal combat between literal enemies.