If someone I know calls I automatically think it's important enough to interrupt whatever I'm doing.
I honestly just think it's the normal evolution of etiquette and societal norms. My grandmother? She answered every call always... that trickled to my mother and me... now? Tech has completely changed in my lifetime, and yah - I screen the crap out of whoever is calling. My kids and their friends don't actually use their phones to speak - they only answer my calls because I'm old fashioned and I ask them to do so.
After some thought, I will make sure someone wants to talk with a text first but it depends on context. If it's a girl I've been chatting with through text and we haven't met, I definitely will prearrange to speak on the phone. If I wanted to talk to a friend of mine right now I wouldn't hesitate to just call. Texting is nice for certain things but it can be incredibly bad when you need to convey information that might require some actual real time interaction for one reason or another. My mom is like sixty and if I need to tell her something and have to rely on texts it's painful if I can't have her immediately respond to ask questions or whatever other benefits there are to speech. Texts can be misinterpreted too if the reader projects a tone onto the words that wasn't intended. I can be really terse and it's efficient for typing on a tiny keyboard with my thumbs but people sometimes think I'm being a pithy asshole. Both have their place. I prefer texting friends as a general rule but I wouldn't say it's rude to make your phone ring. I'm a big boy. You can hit the fuck you button if you want