More nuanced than general 'rudeness', I think we're more in a time of problematic selfishness, ever since covid a lot of people have been living with the type of self-importance you typically only stereotyped with the ultra wealthy.

Its not the trivial being on their phone or playing their music too loud in public, but behaviours simplest put as an absolute disregard for others around them. Social expectations and rules are for others, not them.