ZCL is an offshoot of ZCash. Neither of those coins were part of Bitcoin or related to it. If I remember correctly, it was a dead coin the team had left. A new team came in and took it over. This team decided to rebrand it Bitcoin Private. Then they're using an app separate from BTC to give this new coin to everyone with Bitcoin.
Its not a direct split off the chain. There's no chance of it having some chain confusion the way there were concerns with Segwit because it's not related to Bitcoin. They took an unrelated coin and called it "Bitcoin Private" and are just following the chain to give a coin to everyone that has bitcoin.
That's like opening a hamburger restaurant named "Starbuck's Hamburgers" or a clothing store named "Sak's 5th Avenue Private Clothing Store".
The coin can be great.
The tech and wallets and all can be amazing.
But they 100x off the fact they rebranded themselves "Bitcoin"