Business cards still have their place, and are very "low-friction" - everyone is used to using them, they slip into a pocket or wallet easily and you can write (brief) notes on them (how to pronounce an uncommon name, why you should contact the person later, etc).
You can leave a stack of business cards at a meetup, for people to pick up on their way in or out.
It takes less than a second to exchange physical business cards and there are no software dependencies/compatibility concerns. Also, there's no risk of transmitting malware, corrupt data, or data you don't intend to share when you use paper.
For now, use conventional cards as your primary way to exchange contact information. Certainly explore vCards, but IME people still use and expect physical, conventional business cards. I don't believe I've ever had someone ask me for a vCard, nor offer one to me.