First off, I have no problem using Discord or whatever happens to be the case. 

However, regardless if whether Discord is used or not I do think that it's a user's personal choice to use it. I'm not sure about everyone else, but I RP to have fun. If using Discord, or any Chat program really, makes the RP less enjoyable I'm not sure the benefit is worth it. At the very least it shouldn't be mandatory for someone to use it.