It’s a pretty standard bandwidth/latency tradeoff in my view: email is high bandwidth (it’s in writing, you can re-read, etc.), whereas phone is low latency (several back-and-forth explanations can happen in seconds). Each has its place.

If social anxiety is a factor, that’s a perfectly valid, but separate, issue.

I used to be like this until I got a job that required constant phone calls. Now if I have to explain something using more than three sentences I’d much rather just talk.

I disagree. It really is just way simpler and also in most cases it solves whatever problem you have much faster.