It's always been there actually, at least for some time.
I have no reason to assume anything contrary but for one reason or another I had never seen any warning of that type from Cloudflare before. I am glad they have that protection in place as it acts as a warning to people that could have stumbled across those websites.
The business model for making scam clones is extremely lucrative, as they can often poach hundreds, or even thousands of dollars worth from a single trade, whereas registering new domains for a year only costs a fraction of that amount. So that even if a domain is suspended they can move on to the next one. Server and operating costs are usually static since there isn't actually any infra running.
I would be curious about how lucrative it actually is in USD$ on a yearly basis. If they were not making money, the scammers would have stopped but there seems to be more than enough incentive for them to simply carry on in that cycle of creating a cloned website on a lookalike domain but be ready to duplicate it on another lookalike domain as soon as they get shut down. While all that is happening, they will be hoping to generate as much income as possible by creating as many victims as possible.