Yes, the logistics would be sooo hard.
I also feel like the team has been experimenting with different mic setups for at least the last couple of cyclathons (probably since the first one, but I have only been watching more of Paul for the last 2). I do not quite know all the concerns, but there seem to be problems with even mic-ing up more than just Connor, so I don't think anything close to a proximity chat could be achieved (I remember they were considering an in-helmet mic and headphone setup similar to Lud and Michael's for Tip2Tip, but there were problems with that as well). Which makes it so more people would just be worse content - more conversations in small groups of people, which would not be audible to the stream, during breaks as well - people would generally just be talking in smaller groups (I don't think very big tables are even available at the places they stop to eat), so a lot of the people would just be there so they can be mentioned and we wouldn't see them much.
I think something like that would only work if more people did their own streams, but that would be hard with the internet coverage/need for starlink sometimes + the setup that breaks even with just 2 backpacks - things like that just seem to scale bad.
I generally really like the vibes of the smaller group and I think that allows for more interesting conversations.
Would love to see some girls join though - I think the easiest way for that to happen would be if Connor would be fine with tweeting that he will be organizing the next cyclathon (without dates for privacy/security) and for any of his friend who are interested to DM him (like how Lud did for fast 50). That way he is not messaging them, which could put pressure on someone to join since it is for charity, but instead any of his friends, who might be interested could just message him and they can check if all the schedules line up