I’ve been using Trilium for years and the feature set has grown significantly. It is pretty simple up front but has all the bells and whistles just an extra click or two away. It is entirely free (no up sells, pro tiers, subscriptions, etc - you get it all free, so do support the developer if you can!) There is a third party android app that works quite well if you need that and the pwa is quite good too. I’m pretty sure you won’t be disappointed. it seemed like almost every time I thought trilium was missing a feature, I would find out that it actually has it (or something similar). The only thing I would say is that if you’re a flat file only person, then it isn’t for you - it stores the notes in a database -even though they can be easily exported in a directory format.