This is true, but with the introduction of AI technology, scammers can now be able to improve their writing skills. With AI, they can refine and polish their texts to look impeccable before sending them to their potential victims. Hence, looking out for grammatical errors may not work sometimes.

Also, I just want to add that people should be mindful of the kind of info they share online or on public forums, because that's one of the ways scammers get hold of their data to stage attack.