Atuin replaces your existing shell history with a SQLite database, and records additional context for your commands. Additionally, it provides optional and fully encrypted synchronisation of your history between machines, via an Atuin server.
Yes, you can delete commands from the history. They added a TUI command inspector, which gives you more information on commands (date/time of last run, a time series of command runs, exit codes, etc.). You can delete history entries from this inspector.
In terms of disabling the up arrow remap, it’s just a flag in the configuration file (detailed for each distro in the installation instructions).
I haven’t used atuin a lot yet, but I sure like having a fast, full screen command history with fuzzy search.