I can second this. I use no features except the journal, and it's noticeably slower than it used to be when I first started.
+1. I wish the app had a high performance mode that'd cache all blocks of recently opened pages in RAM. May be had to implement and still retain collaboration on pages, but possible if the mode would also write-lock those pages for the period
What good is many features if they're all slow? You just end up doing everything badly. Notion is for the most part following a bottom-up strategy so they can't simply dazzle some IT purchasers with a feature sheet and ignore user experience.
If things don't get better soon I'll probably jump ship before they get worse.