It greatly depends on your industry I supposed.
I work in the arts space and we do use them.
You’re always out networking and meeting other industry people at arts events.
So, they’re great to have on hand so you can connect with people you meet.
For example, if I have a show, people may approach and want to book me for future shows. Arts events are usually busy, crowded and loud. There might be a lot going on and it’s not a a good time or place to sit and chat about arranging anything. So, I can hand them a business card for them to follow up later.
Works well for me!
Use social media and then the free service LinkTree for a centralized place to keep all of your accounts together and accessible to clients. I have this set up for multiple endeavours and it is a great free system for me!