In general, I heartily encourage people to accept networking invitations. For example, a friend asks if they can introduce you to someone you should know. Or, you get a LinkedIn invitation from someone you don’t know. Or, someone you meet at a conference suggests you grab coffee sometime, and they actually contact you after the event to schedule the coffee date.
Even if you are not sure why the friend is connecting you, or why you’re getting the LinkedIn invite, or what you’ll discuss over coffee, you may find the potential for collaboration, as you learn more.
Meeting new people and expanding nascent relationships can lead to opportunities down the road. (You don’t want to be relegated to just the network you have now, especially if you want to change careers.)
Furthermore, networking is not just for people in active job search mode. If you are happily employed, you can still benefit from hearing what others are working on and what other companies are doing.
You might get an idea that solves a problem at work and accelerates your career. You might hear of an opportunity even better than where you are. Besides, the best time to network is when you don’t need anything.