But what if you're the person saying "Yeaaaaah, I want to get in on that"...how do you? How do I, a casual observer, approach a universe that has about a dozen and a half movies and 6 television series with 3 more on the way? That ads up to hundreds of hours of content if you want to catch up with the entire universe. More power to you for keeping up with it from the very start, but what about John and Mary from down the lane?
You go watch Spider-Man, because it's the first Spider-Man in the MCU. You can go see Black Panther, because it's also an origin movie. You could have gone and seen Ant Man, Dr. Strange, or GOTG in the last several years because they were also origin movies. There are plenty of opportunities for newbies to see movies in the MCU without being confused. If they happened to like those movies, maybe then they could go back and watch the first Iron Man movie or the first Captain America and go from there.
I don't see the issue, if you don't want to invest in the whole universe, there are still stand alone films to enjoy.