I think you both make good points. And again, this is a movie I really, REALLY liked. It's probably in my top ten right now, and my second favorite comic-book movie of 2017 behind Lego Batman. I guess here is where I'm coming from:
Last year(or was it 2 years ago? Everything goes by so fast), one of my favorite films was Captain America: Civil War, and I loved it and told everyone I knew to see it. And for most people, they also loved it, because they have seen most of the other MCU films. However, I work with a mechanic who watched the film with his two kids. He had only seen the first Iron Man but was trying to get back into the MCU because he had heard such wonderful things about Civil War. And he had a bumpy time following a lot of what was going on. So, I was thinking a lot about him as I was watching this film.
I think if you could've added a few lines here and there just to fill out a little more context, it could've stood out as a movie for people who have never seen anything in the MCU to hop into the MCU. Like, seriously, 5 lines of dialogue. Now, you can argue about if that's what the film really needs, and clearly a lot of people don't think that. And, if we're being 100% honest with ourselves, I'm not sure I fully believe what I'm pitching.
I have a son. He's 13. He's seen everything in the MCU (with the exception of the 2nd Thor movie). He loves them. We make a big deal of seeing them. He needed a jumping off point where things were explained to him. For him, it was the first Avengers movie. And I think for a lot of kids, Spider-Man could be that, too.