I do not know how complicated it would be and also how safe to be able to do the autofollow for users who have an account on any platform. But it would make connecting so much easier and device-free.
I believe that most people do have the intention to connect but the current society makes it so easy to be hectic and all over the place. And when two people meet and talk about 1000 things they might end up forgetting to connect and search each other after their username. I feel that human attention span when it comes to new things is decreasing and speeding up the process by using novel technology is something that could help.