I use Silverbullet as the center for both knowledge management and the task management.
Some tweaks are need for me to get comfortable like what is documented in Obsidian like tasks but afterwards it is totally enough for me.
Curiously though I also have strong ADHD but I don’t need the notification so it works fine for me. To me I just visit Silverbullet everytime I feel bored / nothing to do and it works fine for me.