As I understand it, hostapd uses entropy for cryptographic functions, so even though you have an open network (i.e, no password required to connect to it), you would still need entropy to establish a secured, encrypted connection between server and client (kind of like https on a website that does not require authentication). Of course, I could be mistaken about the cause of the issues discussed here and about how hostapd actually works, so it is just an educated guess on my part. At any rate, the source code is available here for inspection: https://w1.fi/cgit/hostap/tree/