Following UI trends doesn't instantly make something better. Yes, it might appeal to a newer audience, but it alienates your older users - especially when the UI trends end up causing downgrades.
I love Discord, I've used it nearly every day for the last 5 years. But these constant UI changes feel like they're changing the identity of the app, something I've gotten to know and grow with for so long. The recent UI change feels like a downgrade in usability, and Tabs just don't feel like they fit in.
I understand that you guys want to appeal to everyone and get new people on the platform, but alienating your old users in the process doesn't sound like a good idea. It feels more unresponsive, and needs more steps to do things that were so easy to do before. Trends, or more specifically following Apple because it literally feels like you're trying to rip off iMessages, aren't always good, and "prettiness" (which is subjective) over usability is never a good idea. I and many others loved how things looked before, and the sheer number of complaints over these UI changes shouldn't be ignored.