Soldier, he went through the whole sugya while driving? I heard from one of his talmidim that Rav Gustman was opposed to listening to tapes of shiurim because it would distract the driver. On the other hand, once a driver asked me to pay with a devar Torah. When I told him that he went into a whole pilpul about why it is really muttar .
As for the social situation now as opposed to in Chazal’s time, we see that saying “shalom” was so important that one could even interrupt keriat shema. Today that is definitely not the case. Yoram Gaon once said a monologue during a concert. He said that he wanted to know if people really cared about how he was doing. He went into a whole song and dance about his supposed troubles and people edged away.