The irony is that the majority of people that need this don’t have the cognitive time or skill to process and set it up for themselves. But the agents and bad actors like North Korean hackers would absolutely have the time and ability to implement and use it. Then you have the market for lemons problem - if requests coming from here are malicious most requests coming from here will be seen as malicious. Aka dark alleys earn their reputation over time.

Not sure how north korean hackers benefit from not knowing who is accessing their servers?

We have Cloudflare Tunnels to thank for this. I wish Cloudflare did more to stop malicious use of Cloudflare Tunnels.

I thought ohttp is opt-in. You have to participate their beta to enable the relay/gateway.

Same applies to Apple's Private Cloud Compute. A service provider has to join the program to avoid reading visitor's source IP.

It will handicap service provider's capability if I am not mistaken.

I think you misunderstand. This is for inbound traffic, not outbound.