the shift happened differently depending on who you were talking to - don't assume your friend group's timeline matches everyone elses. what people miss when they look back at this is that email didn't really *die*, it just got partitioned: work emails stayed put and got more formal, while casual stuff moved to instant messaging. the mid-2010s is right, but it wasn't some sudden flip - it was more like 2013-2017 was the transition window where you could still catch people via email for plans, then by 2018-2019 most folks had just stopped checking it for anything urgent unless it came from a boss or a service. the smartphone thing mattered, but honestly the bigger factor was that group chats and discord servers let you have an ongoing conversation thread instead of the awkward email chain hell where replies got buried and you lost track of who said what.