I've used discord for a number of years, and use it almost daily with my friends. Arguments over UX will always be opinionated, but one thing where discord absolutely shines is voice chat. There's just no competition to any other voice chat system out there; it's fast, it's high quality, and most importantly, it filters out non-voices. Clapping, water faucet, vacuums, crunching chips, coughing, breathing, desk noises, none of it comes through and all of it gets filtered out. It makes for a significantly better experience when I don't have to deal with someone else's "voice chat etiquette" incompetence/ignorance.