I've done some written interviews in the past. Sometimes it's this "pen pal" format: someone asks a question and the response comes in a couple days later.

An old hobby I used to have was asking questions to interesting people I hear on radio, from talks on YouTube, or books I read. People get on radio to be listened to, so nearly all of them are happy to respond.

You do have to keep a little momentum... they're very likely to respond to something they just did a day ago, less likely after a year. And back and forth can be nice, but there's only so long they'll do it.

Some people used to insist on calls but just agreeing on a time could take days.