Another help is to fill in the recipients AFTER you finish writing the email. That way you can't automatically hit send when you finish writing the text, helps make sure you do a quick double check that everything is correct
But like so many things, I feel like this feature has gotten worse over the years. Seemed to be fairly accurate for some time, but it honestly wouldn't surprise me if they've made it shittier with "AI". Now I get more false positives than anything, and the one time recently I did actually forget to attach a file, the message didn't even show up ... I guess because I said "I've included the latest copy" rather than "I've attached the latest copy"?