If Inno would have some techies with time on their hands to work on a chat function, the priority should be the ingame chat function.
To be honest: it is quite poor.
We can only read back 50 (?) posts. - After a working day, thats way too little in a very active FS.
We can select and copy some lines, but just very little and only on browser.
We cannot post url's. Oh wait, we can but with the domain name blanked out: **** As if we cannot type 'youtube' in the next line.
We can use icons, but only with Win10 (as far as I have seen).
And a properly working chat function is not a luxury in this game, knowing that in FA's, Spire an Tournaments we need to cooperate well and therefor need to communicate a lot. A smooth working chat is a basic need to do that.
Rather than just adding a 'world chat' to this forum, I would propose an overhaul of the communication ingame. For example to use a proven tool like mIRC. For an example see here:
https://www.mirc.com/ or see
https://slack.com/ for an integrated example.
And then, adding a world chat could be an option.
In case anyone is afraid of abuse and players misbehaving in a general chat: it can be moderated.