The problem with Calendar (as with Music etc etc) is that they are forever adding new features while failing to address the basic problem that the front end always truncates entries and doesn’t actually show you sufficient information to be useful
Adding modern functionality to apps like Mail & Calendar shouldn't make them any less easy to use. Unfortunately Apple's approach is to keep the app looking exactly the same as it's been for the last 10+ years but just bolt on added functionality which just makes things confusing or annoying for people.
Mail, Calendar, Reminders & Notes are in urgent need of a complete modern revamp. If it upsets a few people along the way, so be it. Apple's stock apps are so far behind the competition, it's not even funny anymore.