To state the obvious: my personal preference is to run Debian GNU/Linux. My current workplace is a CentOS shop and usually I'm the first to claim that it doesn't matter at all, and distribution specific implementation details are irrelevant for what we do (running a JVM).

Let's take a short detour to the RedHat network-scripts. Two weeks ago we found some systems we originally installed in a different network segment, with different DNS servers and different search domains, came back up after a reboot with a rewritten 'resolv.conf'. Later on cfengine replaced the generated 'resolv.conf' with the intended one, so it wasn't that obvious to spot in the first place. A colleague found the origin of the rewritten 'resolv.conf' in a device specific configuration file that defined the 'DNS{1,2}' variables with the installation time DNS server IPs from the other segment. I expected to experience the same behaviour (resolv.conf rewritten during startup and replaced by cfengine later on) in other locations, but assumed we just didn't notice it because the main difference would be a slightly different list of search domains. And I was wrong. I checked the timestamps of several 'resolv.conf' files and their cfengine backup file. None were recently created or related somehow to a reboot.

grep-ing through parts of the network-scripts I found the following conditional in '/etc/sysconfig/network-scripts/ifup'

if [ "$PEERDNS" != "no" ] ||[ -n "$RESOLV_MODS" -a "$RESOLV_MODS" != "no" ]; then
   [ -n "$MS_DNS1" ] && DNS1=$MS_DNS1
   [ -n "$MS_DNS2" ] && DNS2=$MS_DNS2
      if [ -n "$DNS1" ] && ! grep -q "^nameserver $DNS1" /etc/resolv.conf &&
         tr=$(mktemp /tmp/XXXXXX) ; then
 ...

So if you adjust only the second nameserver IP you stored in "DNS2" in your configuration you end up without an update to your 'resolv.conf'. Now knowing that, I'd say this is relevant distribution specific knowledge, and I'm wondering how many of such subtle behaviours we've hidden in Debian specific solutions? Maybe knowledge about distribution specific implementation details even matters after all.

Regardig the 'resolv.conf' issue itself the fault is on us. We as the responsible team did not read the documentation properly and thus deployed a configuration that later on let to some unexpected consequences. I try to remember those issues as an example for the next NetworkManager/systemd-networkd vs old-school-network-scripts argument.