Well, here's what we have to remember, unless you are watching a movie based on an historical figure or event, movies are not real. If we take Notting Hill as an example, that was about the internationally acclaimed movie star falling in love with the bumbling but well-intentioned bookshop owner. But that very rarely occurs in day to day life.
Your theory, also, is predicated on the belief that two people want to get together but are afraid of how to approach it, and yes, sometimes well-intentioned friends play cupid, especially if they can see what both parties want.
One of the things you MUST remember is, and I describe it as being like an opportunity I had at school. For three pieces of assessment in English, I scored 6/10, 8.5/10 and 8.5/10, and I chose to improve on the 6/10 and did a second piece and got 8/10. Had I scored 4/10. the four would have counted towards my final grade. So, if one person wants a relationship and one person wants a casual friendship, well, it's basically, a casual friendship, take it or leave it.
Yes, you can get out of the friend zone, but not necessarily with that person. Now, I remember a story about a Jewish couple in early Nazi Germany, they were engaged, and the man, who was a hairdresser, went to Shanghai, China, and the woman went to Australia. The man awaited passage to Australia, but it took too long and both met and fell in love with other partners. The man came to Australia, and reconnected with his ex-girlfriend. And after her husband died and his wife died, they consoled each other, but their romance was rekindled, after 50 years. And they married. The difference is, they had a relationship to begin with.
And, yes, sometimes, at say a school reunion, if a woman at school fancied a sporty guy but she married one and was treated badly by him, so she divorced him, and found that the geeky guy at school, who's still single, is an attractive proposition, and they get together, that can happen.
The only way, though, to get out of the friend zone is not if one person is persistent (what can happen then is the person says yes to a date, but they only say yes to get the person off their back and neither has a good time) but if two people want the same thing with each other. And let's not forget, if a guy starts dating another girl but he still has eyes for the first one, the second one might see through it, especially if he's "Girl One this," and, "Girl One that," Girl One, if she hears about it, might well say, "I'm happy for him."