Recursively changed the rights?

Question

linux

In the park, for the /usr directory , I recursively changed the rights
sudo find /usr/ -type f -exec chmod 644 {} \;
, it’s good that there is a flash drive with linux at hand,
you
don’t need to set 777 for everything, as I understand it, the
/usr/bin and /usr/sbin directories will be enough or something else? (well, in /usr/local/bin only search and apt )
please take a look what are the rights in bin sbin ?
PS
fixed it :), in order not to think for a long time, I set 755 fsem files
additionally set SUID SGID

these /usr files

$ ls -Rl  /usr |grep -E '^.rws' | awk '{print $1 " "  $3 " "  $4 " " $9}'
-rwsr-sr-x daemon daemon at
-rwsr-xr-x root root chfn
-rwsr-xr-x root root chsh
-rwsr-xr-x root root gpasswd
-rwsr-xr-x root root newgrp
-rwsr-xr-x root root passwd
-rwsr-xr-x root root pkexec
-rwsr-xr-x root root sudo
-rwsr-xr-x root messagebus dbus-daemon-launch-helper
-rwsr-xr-x root root polkit-agent-helper-1
-rwsr-sr-x root root VBoxHeadless
-rwsr-sr-x root root VBoxNetAdpCtl
-rwsr-sr-x root root VBoxNetDHCP
-rwsr-sr-x root root VBoxNetNAT
-rwsr-sr-x root root VBoxSDL
-rwsr-sr-x root root VirtualBoxVM
-rwsr-xr-x root dip pppd

Answer 1

find /usr/ -type f ! -perm 644
You can run such a check on a healthy system.
I'm afraid the result will upset you: in addition to bin and sbin, there are a lot of differences in lib, and in share, and even in src.

Answer 2

not at all, not even the fact that after that it will work to
get this folder from the backup