For I2P they probably know close to all 20k IP addresses, for Freenet it is not likely that they do. Hidden services are still weak to correlation attacks, it just might be a bit harder for an attacker to be positioned to carry them out. I definitely think SR users are safer on Tor than I2P. The fact that I2P users are easily enumerated by itself makes Tor better for SR vendors. If SR vendors used I2P they would be quite fucked, as their crowd size is already "the people who are in this small geographic area where packages are shipped out of". If their crowd size was "The people who use I2P in this small geographic area where packages are shipped out of" they would be totally fucked, and using I2P would result in that scenario. However, there is an argument that people who do not leak their rough geolocation are safer using I2P in some ways. They are definitely less weak to timing correlation attacks than Tor users are, and that is a big advantage. On the other hand they are also far weaker to intersection attacks than Tor users are, due to the fact that they are so easily enumerated. Hidden services can have down time without their anonymity being hurt much if at all, Eepsites that have down time can quickly have their anonymity set size reduced or even eliminated. Tails has a version of Tor Browser that also supports I2P.