In theory, member directories are fantastic.
Members can search and network with members who match a specific criteria – like being in their location or possessing unique skills and experiences. Members can find precisely the people who can help them.
In practice, member directories rarely function well. Even when they do, they’re rarely used. How often have you genuinely tried to find people matching a particular skill set or location? And when they are used, they’re mostly used by spammers and recruiters (which in turn lead to those with expertise hiding their expertise from directories).
As strange as it might sound in this day and age, asking around still yields better outcomes than a directory. Fortunately, within a community, reputations naturally develop and spread. It turns out asking around is exactly something a community supports well.
Don’t base your technology decisions on whether a platform does or doesn’t offer a member directory. If you build your community right, you’ll have a natural directory anyhow.