Apple has for political reasons disabled the possibility to install a Flash plugin on Safari/iOS. Why doesn't Firefox do the same with a CDM component for political reasons?

Mozila will never have the marketing firepower to pull off such a boycott.

Apple disabled Flash for "security reasons." You can certainly read in politics, but the reason they gave was that it was the #1 attack vector on Macs and they had no way of securing it. And more importantly, nearly everybody else was on Apple's side in this fight. Other browser makers had problems with Flash too. Mac users largely hated Flash because it had terrible performance on that platform. Even Adobe was cooling off toward Flash as it became more and more clear that it wouldn't work on mobile platforms.

Mozilla's position here is not at all similar to Apple's position then, so their options are not the same.

The cost to the user of switching off Apple hardware is much greater than the cost of switching from Firefox to Chrome.

A few years ago there was a cost involved for switching to the iPhone. The only reason why you see this the other way round is that "no Flash" is now established (at least for mobile). On the other hand: no DRM in browser cannot be considered as established - so we are at the same point where the iPhone was some years ago.

Apple also did this for performance and usability reasons. And when Apple did it, there were no smartphone alternatives that provided a sufficiently good Flash experience.

And before you say Android had Flash, I had an Android device that could run Flash in 2011. It was a pretty useless feature.

Saying that Apple "disabled the possibility to install a Flash plugin" implies that that possibility existed at some point. Support for installable browser plugins has never existed on iOS, so there was never anything for Apple to "disable".

Adobe offered Apple an iOS port of Flash and Apple had Access to beta versions of ports. Thus Apple could have enabled the option to install it by default or as option. But for political reasons Steve Jobs/Apple decided differently.

Is there a way to disable all related code in Firefox itself? Just for the sake of it. May be Mozilla can produce clean and tainted builds for that purpose.

The code is 100% open source, so even if there isn't a GUI option for it, it would be easy for people to make builds without it. There are already many forked builds of firefox like iceweasel, etc.

Yes, I expect such thing to surface, but it would be nice if Mozilla could provide such options on their own too. That would be some small positive gesture towards those who don't appreciate their move and see it as a betrayal of Mozilla's core values. It would as well make this issue more apparent. Doesn't Mozilla care about educating the public on such matters? It surely would be a positive thing for the Open Web.

As the blog post mentioned, the EME stuff will be an option that the Firefox user would need to agree to install. That would be an opportunity to educate users on the topic, I think.

I meant it a bit further. Not just disabling the EME external module, but disabling all related code in Firefox itself on the build stage. While functionally it won't make much difference, it would have more of a symbolic nature of making a point. Plus such builds would guarantee that it can't even be enabled at all (without user's knowledge for example).

If there would be build switches to disable that, I'm sure Linux distros with similar to Debian policies will ship versions where it will be disabled altogether.