I am about to leave YNAB because I am using version 4 (standalone software) which is 32-bit only. My main machine is a Mac so I won't be able to use the software with the next major version. Also, I do not want to use the new YNAB web-based app because the privacy policy is contradictory and their subscription offer is just shitty.
Currently I am using Outbank, which is more like a banking app but has automatic categorization which is quite cool, and you can define budgets. Still, no suitable replacement. I really hope for Firefly to take off with a powerful budget planning somewhere in the future.