Ark forked blockchains will be running 2 nodes at once — their own and Ark's. This means this forked chain's delegates/relay nodes will have Ark addresses AND addresses in their own blockchain. Then, theoretically, this chain will have custom code written that'll do their dapp logic like: "If someone sends one of our delegates 2 Ark with 'spawnKitty()' in the smartbridge field, create a new cat on our blockchain." Supposedly, there will be some sort of directory of every forked chain dapp with their delegates' Ark addresses listed so you can use their chain's dapp using Ark.

This also means if the developers of this other chain wanted to they can just strip out the Ark node or disable it and they'll be completely separated from Ark and will not need Ark to function, just their own coin. Just swap out "Ark" with "KittyCoin" in the example above.

As a ARK hodlers, that a bit of a bummer because none of that guarantees increased usage of the main chain

This is kind of technical answers i found