Depends on the human.

I would use that turn of phrase (needs no XYZ) — but maybe not in the context of system prompts, perhaps. Though I don't know; sometimes a flourish is a nice thing.

You might be right that the clash of that vernacular pattern and technical language is a "tell", but AI did learn this stuff from actual people; a lot of the time Claude reminds me of an actual person who worked for a firm I worked for in the 90s, who wrote in an annoyingly gnome-wizard style.

Ultimately it's the volume of these problems that is the tell.