Yeah, unless I’m missing something the author would have the same outcome with regular pointers if he’d freed them at the same time (one at the end of the anon scope and one at the end of fun1).

That's basically it. The way the blogger wrote fun1 means the pointer is freed once the function exits, because they explicitly added the std::unique_ptr to take over its lifetime. Afterwards they are surprised by the fact that it really took over its lifetime.

The weird part is that the blogger had to go way out of its way to write that bug.

I almost can’t believe it’s legit, it seems like such a basic, fundamental misunderstanding of concepts it’s like chatGPT output.

I agree. It almost sounds like one of those coding exercises recruiters throw candidates in preliminary hiring rounds to weed out the bottom 5% that have no idea what they are doing.