I always thought the magnifying glass for search made sense as it was like a detective looking for clues.

It is shown in the famous Cluedo board game [1] (aka "Clue" in the USA). It's typically associated with forensics when looking for fingerprints.

[1] https://upload.wikimedia.org/wikipedia/en/6/61/Cluedo_1956_S...

I don't think you don't have to internalize it necessarily. I'm going to continue to care about and use Standard English spelling and grammar, and it's ok to notice when someone uses something slightly off-standard, as long as it doesn't affect anyone else or interfere with good-faith conversation.

I run a specialized search engine myself and I had no hesitation in using the icon, only because it's a well understood symbol.

Any idea what a better search icon would be?

Binoculars were used decades ago. Not sure if they're still used. Ditto a little funnel for filtering.

Definitely agree that binoculars are less conspicuous, the magnifying glass can also mean zoom. But, I think users are (for better or worse) used to the magnifying glass.