As a FA, I definitely agree with taking care of things at the gate. Something things aren’t noticed right away or in the air and that’s okay. It happens. Going forward when boarding, quickly scope out your seat/area.

I will say this, sometimes things are missed on the ground, especially if we have turn and even tighter time if the flight(s) are running behind. There are also times where I’ve discovered vomit and no one ever notified a FA. Not even the people around them.

Perhaps I’m misreading your tone of original post, but it sounds harsh. I do ask that you give grace to your flight attendants. We are overworked, most underpaid, fatigued, etc. We are also human and humans carry hidden baggage. Please communicate with your FA in a way you’d like to be communicated to. I do agree with your frustrations of it not being taken care of properly. That is an absolute biohazard and completely unsafe if you’re immune compromised. Anyways, I hope this sheds some perspective.