I don't understand, Its alway's nice to have a dedicated site but I'm not used to this,
A new site with repost of another sites that begs to move there feels like hey lets
not burden yamahasynth.com. Montageforum does look better equipped for every
aspect of the Montage but I'm like a bunny watching if picking that carrot is save.

We hear you.
The goals are to have a place for a genuine community. A place which could exist alongside Yamaha synth and the Facebook group. A community for a synth, basically, like EX5Tech was, like korgforums, like Rolandclan, is to know the other users, be able to PM, be able to share sounds with one another, and to preserve.
It's a categorized forum. The intention is to have everything neatly in its own place.
Not all posts are reposts, but many of the technical ones are, with all credit given of course.

If you buy today a synth from yesteryear (from 10, 15 or even 20 years ago) it changes the world if it had good, categorized, searchable forums or not.

It's okay if you don't like this, you don't have to. Eventually the community will grow and it will have much more.
Again, Yamahasynth forum is great, and it will keep leading everything technical support about the Montage.
I am pretty sure Yamaha are not going to try to tell people that all this information about Montage should be ONLY available to people who visit their own site?