If I am dating a woman and she is texting another male, it will probably bother me. However, I will also tell myself that "Eh. She is with me, and that is enough". Now, if I see that the two are getting more and more intimate and all, then I know I need to speak up. Back to the fact that it would bother me........what I mean here is that that little thought of "she could be cheating" might creep in to my mind. But it is a thought....and I would dismiss it simply because I chose to be with this person....and once I go all in, I give a hundred percent trust.

Well .. personally I won't get jealous .. just that would be the last time to date the girl who has much more important things to do than focusing on a mutual conversation while being with me in somewhere nice ..

Fast answering to messages has something in common with texting while dating .. it shows lack of respect to an other person .. and their valuable time. If you are busy and can't reply right away, would be nice to let the other party know .. otherwise you're just wasting someone's time, who expects you to be a nice person.
So, perhaps before accusing guys in jealousy would be wise to look in the mirror ... just saying ...

What he said