I agree that history can be boring. Today's films are flashier, maybe a little easier to watch. Certainly to most people today if they have to pick between watching an old black and white movie and a present day one, they'd choose the present one.
I agree that films have generally improved over time; imo, as more and more films have been made, the understanding of what makes a good film has gotten better.
But neither of those things mean you should just write off the entire history of cinema. You don't need to understand it to judge today's movies, but it seems pretty ignorant to just throw it away. The fact that movies have "got better and better" doesn't mean all old movies are worse than today's. Ask most people what their favourite movie ever is, and it's probably going to be older than you are.