Comment 4 for bug 1827753

@chaitrex, IMO the workaround proposed by @ddstreet in #2 is the simplest solution, overriding default configuration by placing a configuration in /etc and this also follows the general concept of how systems should be configured.
The big miss here is not having the behavior documented in modprobe.d(5).

Since the file in /lib/modprobe.d can be overridden by placing an identically named file in /etc i don't think that making the file shipped in /lib/modprobe.d is necessary or desired.
Also we would like to go in the direction of not shipping files in /etc by default, so moving the file to /etc would be a step back.

As a side note in similar situation the system administrator can use dpkg-divert to keep a file from being overwritten by a package upgrade.