If you remember using teamspeak or ventrillo… Their is a FOSS alternative called mumble that works similarly. Its essentially the closest to what you’re asking that has both VOIP and other features. Some communities especially mmorpg clans and gaming clans still use it. Idk how popular it is in general though. Discord is supported by huge donations which is why they’ve been able to dominate, but teamspeak/mumble still exist and essentially are the same thing but less modern.
IRC and Matrix are both IM systems but are alternatives to discord if that’s all the functionality you seek. Matrix is also in the fediverse.
Living in Florida I feel it’s more common to see publicly. Recently join a “Walk for Heart Health” type event and it started with the national anthem and pledge. Local army ROTC high schoolers also came by a did… some form of rifle performance. This all was to “kick off” the event and most people had hands on their heart type stuff the whole time. Not to mention the city has “Land of the Free” flags on all the light polls in that plaza and it was interesting just HOW MANY people in florida wear those 1776 shirts or the “F around and find out” shirts still.