Firstly, this has been suggestion multiple times before so if you are going to suggest something in the future again, please check if there is already a thread about it that contains exactly the same.
Now my opinion. This is a yes and a no for me.
People often hung around and chat with each other in lobby 1 of SkyWars for an example. Nowadays, that’s not really the case anymore. Often, when I join lobby 1, it’s just quiet and everyone is doing their own thing.
On the other hand, it’s useful to just have one lobby where you can choose to join games. The reason for that is because when you want to join your favorite EggWars map but it’s not available, you can just run a few blocks and easily join another game mode. This used to be a lot more difficult because you had to travel much longer.
Besides that, the lobbies are pretty much always filled. This wasn’t the case before.
Long story short: I think it should this way because for me there are more advantages than disadvantages about having one lobby.