Honestly having more potential communication platforms could be handy because if someone's not on one, they could be on one of the others. For example, if you can't find me on the site cbox, i'm usually on skype, and if you can't get to me on skype, i'm usually on tumblr (my url is solilo-jay if anyone is interested |D). The more communication avenues we have, the more likely we are to find the person we want to talk to. Plus, having a discord server will help anyone who perhaps does not want to use skype feel involved by being part of the discord pmd chat.
As long as all areas are kept updated on current site affairs, I don't see why having multiple 'chat rooms' per se would be a problem at all as even when you can't get in touch through skype/discord, there are still site PMs.
I'm not here to debate with Lord E V or anything (super sorry if it comes across that way >.<), i'm just here to point out that although there are negatives as he describes, there may also be positives to be had here. Both discord and skype keep any messages sent to you as far as I know so unlike the site cbox anything you say on either site will get seen eventually.
If people don't want to use both, or don't want to use skype or don't want to use discord, that's fine. But I don't think we should eliminate that other avenue when others have outwardly stated that they much prefer it. I encourage any members who are reading this to just use whichever platform you are most comfortable with. The discord pmd chat might not thrive immediately because it is true that many members currently use skype and others might not want to attempt transitioning to another platform or don't want to have to keep up with more than one, but I personally will try to post updates on both skype and discord as well as on the site itself.
If it turns out that no one uses discord, then we can just shelve the idea, but I don't see any harm in trying it out ^-^