If you can use zsh instead of bash, then it's a lot easier. Zsh can match files based on their attributes through glob qualifiers.
**/* searches subdirectories recursively. The parentheses after
* contain glob qualifiers:
D to include dot files, and
m to match files based on their modification time in days like
find -mtime (you can also choose a different unit and make the time a limit, e.g.
(Dmm-$min) acts like
find -mmin -$min).
Zsh is preinstalled on macOS. On most other unix systems (in particular most Linux distributions), it's available as a package but not installed by default.