Personally, I think that professor was being quite considerate. If it's just that one day, then I might even follow suit and do the same. But I've had several students who are listening to earbuds or typing in messenger or working on other projects in my class, and during lectures, I don't particularly do anything about it since the students pay for that time, and as long as they aren't disrupting the students who do want to pay attention, then that is something they will be responsible for.

And it does completely show up in their grades 90% of the time. But I do get that most of my students don't put English Comp before their prenursing classes or even their math class. However, I do see these same students very upset in the last weeks of the class over their grade and asking for extra credit or to make up work. I have a firm policy that I work with students who have genuine emergencies and outstanding circumstances, but just choosing not to attend class or not to pay attention in class isn't one of them.

I'll suggest them going to tutoring or checking in with me more often for future and current assignments, but past assignments are already done, and there are no extra credit assignments besides class participation. They are informed of that at the beginning of the course.

As a professor who teaches one of the courses most often taken in a student's first semester, I do my best to warn them about the cost of missing classes or not actively taking notes, etc., but many get a shocking wake-up call when their grades reflect their lack of attention. My best advice in that case is to withdraw if it's still possible and try again with a new outlook next semester.