Is shoutbox a desired feature in multiplayer PBBG - and what's appealing about it

I've been having a conflict of opinion with my codeveloper about the nature of a chatbox we want to include in the game we're designing.

The nature of the game is creature breeding and training + economy, and I want to include an inbuilt chat/shoutbox that would enable communication between logged in players only - To have a place for players to communicate within the game context more easily, and be able to visit ingame profiles of people chatting in a straightforward way by clicking their name in the chat.

We generally agree on the necessity for the real-time communication tool but we had two disagreements:

• my codev initially thought of just integrating discord into our page - though I was pretty adamant that having both would be a better solution - because having just community discord as a stand-in for a chat space, from what I've experienced in other games tends to accumulate players chatting that are no longer active in the game or just currently not logged in- which is not bad because that's building a community But shoutbox fullfills a completely different option, which is more direct exchange within the context of the game - like advertising your sales without the necessity of posting links (as your name in chat would directly link to your in-game page.) or more shortform conversations or shoutouts.
• Also codev thinks the shoutbox HAS to automatically update itself - while I think just having a manual update button is good enough, maybe even better if it won't require us to manually code more functionality, like making sure the shoutbox doesn't move from the spot you're reading with the inflow of new messages

What do you guys think? Is a shoutbox something you like to have in games, and what range of functionality is preferred/desired for it?