What the opt-out actually does
The PimEyes opt-out suppresses you in PimEyes results. It does not reach the websites hosting the photographs. If a conference gallery, a press release and an old forum thread all carry your face, those pages are untouched by the opt-out and remain exactly as public as they were.
This distinction matters when you are deciding whether the process is worth the effort. It is worth it, because the search engine is what turns scattered public pages into a single queryable identity. But it is a de-listing, not a deletion, and expecting deletion leads people to conclude the process failed when it worked as designed.