I can attest to this, having gone through pretty much the same cycle of apps and wikis. Finally settled on plain text files with cloud sync. Except I use a bit of YAML to give the material some structure.
But I use this to write down things I would consider more 'information' than 'knowledge'. If it's a new cloud app I found on HN that I might need later, I write it down. If I learned something new (for example, I recently learned about phage therapy as an alternative to antibiotics), I resist the temptation and try to integrate it into my existing body of knowledge. In my opinion, if you have a 'fact' that needs to be memorized, then it is either a bit of arbitrary information or it is not yet tethered to the rest of your knowledge and is therefore banging around in your head. I usually find a link to nail it down. I wouldn't exactly call it a 'memory palace' but it's sort of like that.
But I use this to write down things I would consider more 'information' than 'knowledge'. If it's a new cloud app I found on HN that I might need later, I write it down. If I learned something new (for example, I recently learned about phage therapy as an alternative to antibiotics), I resist the temptation and try to integrate it into my existing body of knowledge. In my opinion, if you have a 'fact' that needs to be memorized, then it is either a bit of arbitrary information or it is not yet tethered to the rest of your knowledge and is therefore banging around in your head. I usually find a link to nail it down. I wouldn't exactly call it a 'memory palace' but it's sort of like that.