pdboddy:
Be careful with that. It easily leads to "Hey, I see you on Discord playing Counter Strike, and you've not posed your reply to the new scene I posted an hour ago.."
And well, if they are ignoring you on RPoL, they can ignore you on Discord also. They can also set themselves to appear offline.
And some aren't comfortable handing out their socials to someone they don't know.
True, but it makes ignoring you less likely. As for the threat of "they might see you on..." I doubt it very much. First off, I rarely turn Discord on, personally. Second, I don't tell them mine. And third, even when they inevitably find it out because I have to contact them, I am always listed as offline. I can respond to messages at my leisure.
To your last point, that is their choice. They don't have to hand out their socials - but I don't have to let them in my game. I don't charge money to join my games, but I do have requirements. I also don't let characters play Antediluvians in a vampire game. It's just one of the rules. *shrugs*
Advisor:
If you are doing that I would suggest setting some ground rules. Like if the posting period is once a day I will only chase you on discord if you have been silent for 2 days. You could make a discord group rather than just asking for their ID that way everyone can talk in there instead of an ooc chat which might promote engagement.
Meh, for me it takes a lot longer than that. I prefer daily posting, but it would take at least two weeks of radio silence - maybe more, depending on how the game is going - for me to reach out through Discord.
I'm not averse to a Discord group, except
I am not on Discord all that frequently, and I'm not really familiar with it enough that I want yet another thing I have to keep up with. I'm old. For me, it's a high tech version of AIM.