Defines on what you mean by 'playable', apart from the Linux issues which do make it more unplayable.
Does the game run and operate - Yes, with rare CTDs since 2.3.
Is the game usable - Yes, if you like an easy life.
Is the game working as designed (WAD) - No, but it is playable, but not as you might expect (and apologies, but I only started with CM, so I have no experience of how it used to be).
I have various armies scattered around my empire, but, with High CA, I don't see my counts warring on their dukes. I do have a lot of intrigues, generally Kill Someone and some Claim Fabrication. If not that, they are all buried in seduction, which is an issue with WoL. I get an occasional revolt, Cathar or Sunni, but no-one has tried for Independence or Lower CA. I had a couple of Adventurers against me in the 1000s but nothing else since then, apart from raiding Vikings. Perhaps because of my size, but no-one wants to declare war on me.
France/Benelux split into 6 kingdoms in late 8000s and all they seem to do now is deal with revolts, very few internal wars. None of them or Italy were interested in the last Crusades for Greece and Jerusalem, so I grew from King of Bavaria to King of Bavaria, Greece and Jerusalem, and have the Bavarian Empire. I am, apart from Umayyad, the largest army at 1185, and waiting for a Jihad on Jerusalem.
There are things I could do - take out the rest of Europe, Greece, Anatolia should all be possible for me. It is just that I don't get attacked, internally or externally.