But yes, if someone doesn't answer and then starts a text, it should be assumed/checked whether they're busy.
Consider how most people communicate now a days. A call is only for long conversations. No one is expecting to receive a call without a reason, out of the blue. I could certainly imagine people texting back, confused about what their friend wanted to talk about, and whether they could answer in a quick text instead.
That's not anxiety, it's just practical. No one is expecting you to call just to say "hi", they assume there must be some sort of problem that you want to talk about in depth.
It is my opinion that it is unhealthy, and that people should be aware of that and do more to be less unhealthy when it comes to social interaction.
I think it should be worked on if the person in question would rather have an easier time talking on the phone. Otherwise I'm not sure I agree.
I'm autistic and phonecalls are a nightmare given ambiguous social signalling over who begins speaking and when. Thankfully at this stage in the game most people contact me via some other communication method, the only calls I get are scammers.
I’m the opposite. I tend not to text. Most of my friends and family know this and call. When someone does text me, I remind them gently that I’m not willing to sit there trying to type on a tiny screen to have a mediocre conversation with them when they can just call me instead. I say it in a nicer way of course. It’s never a problem! I guess I’m just old but it looks like the default is shifting towards texting lately. No offense to the texters, but it’s just not my thing.
And most of the time, I love to have a phone conversation.
But, the mental state is not always there for it. I may may be in a low mood, or emotionally exhausted, or a host of other reasons why a voice conversation would not be ideal right now. When I talk to a friend I like to be able to engage with them and give them my best. Sometimes, it's just not the time.
So in such a case I would prefer to speak to them later, perhaps the next day after a good night's sleep. It shouldn't be a big deal unless someone makes it into one.