I'd think about this from two angles...

1) Who are the people you can get to start using the platform IMMEDIATELY? Think your friends, network from college, or even LinkedIn connections. "Prime the pump" with people you know at first, to help get the network growing.

2) The point of a MVP is to quickly test a product idea, and iterate until you have a compelling product. I have a friend who runs multiple 7-figure businesses, and he says that he always looks for a "wow" reaction when he shows off a product — even a MVP, if it's just the concept of what it can accomplish. Remember you don't want to build more than you need to at first. A good product adapts to what gives the most results to your users.

Hope this helps! If you need any additional help, feel free to book a call. I recently grew a MVP to six-figures ARR, so can share the things we tried.