The more people there are the harder it seems to bring up something new because multiple people want to talk. If that happens often at your meetups it might be time to split the group into two.

If you do want to have discussion with 5 plus people you can have a moderator. Roberts rules of order would seem appropriate. LW people usually are good at following fixed rules.

In environment where there aren't fixed rules, I have found body language to be a tool to signal that I want to talk. I change my posture to be more upright and come forward. I raise my muscle tension. I take up a bit more space. I hold stronger eye contact with the speaker.

If I do this I often manage to look like I want to speak to other people. It's still requires other people to give you the word, but getting the skill of looking like you want to speak down helps you also outside of LW meetups where you can't trust that people know why you took the poker ship.

Sometimes there a situation where pauses between speakers are very short and I need 3 seconds to form a sentence and get speaking. In those situations making a gesture such as putting your hand on the table can signal to other people that you "take the floor" before you actually speak.