Ok, but there is a massive difference.

The point of Nostr is to achieve resistance trough decentralization: even if some relay fails, or deletes your notes, they remain available as long as as some other relay continues to store it.
Obviously even that which is on relays won't last *forever*. The sun will explode some day. But it does have a kind of resistance which isn't achieved without decentralization.

Nostr.build, despite the name, has nothing to do with Nostr, relays, or decentralization. It's a classical centralized image hosting platforms, like we've always had. It's not censorship resistant, it's just a plian-old image host like we've always been using.
Linked images don't become "immortal on Nostr". Not only are they not immortal, they aren't even *on Nostr*, they are just on a typical image host and there is a link to them on Nostr (a link which will become invalid as long as the host goes down or deletes that image).

I can link Reddit on Nostr. There: https://www.reddit.com/
Did I just make Reddit immortal on Nostr? I don't think so.

There absolutely can be resilient censorship-resistant ways to distribute images using decentralized systems, but placing them on a typical image host and linking them on Nostr isn't one of them. 

 I got it, I said you are right, I got the concept wrong you are right. Ok?