If you create a directory and a file like this
mkdir 'x ./'
touch 'x ./ x.c'
and try the find command, you will have a match
x ./ x.c
Now if you pipe this into xargs rm you don't have just one path. You have
The middle one is the current directory. So all will be gone.
You are right. The command is not safe.
But you should anyway understand a command before using it.
The sudo command seems pointless here. Giving recursive flag (-r) to rm
doesn't make sense since you seem to have been only trying to delete files,
not whole directories. In the example I gave having rm without the flag would
only delete the .c file.
Hope you get your files back.