But the cable co's are now encrypting to make cable on all but a few channels making it impossible for me to view on the platform of my choice.
The reason for the cableCard you claim you have more than one of is to do the decryption of content. If your cableCard isn't decrypting the content you are paying for, it is broken. Call the cable company and get it fixed.
I have an HDHomeRun with a cable card, and VLC talks to it just great on Linux. At the point it hits the net it is unencrypted and ready for many different viewing programs. I've even got a DLNA (IIRC) app on one of my Android tablets that can view the content from the HDHR.
Fellow HDHomeRun owner here. It was my hope that your description would be the case. I initially made my setup with Mythbuntu, and then I learned about the CopyOnce flag. The use of the CopyOnce flag is prohibited on the broadcast channels, but on actual-cable channels (not even HBO/Showtime/Starz), it's up to the cable company as to whether they want to use it. My cable company (Altice, formerly Cablevision) sets that flag on all their non-broadcast HD channels, and over half of the SD ones, not including premium channels. It worked for the two dozen or so channels that didn't have the flag, as did VLC, but virtually every non-network show I wanted to watch was on a C1 channel. Mythbuntu can't use signals with the CopyOnce flag, and it never will because of the licensing requirements (no one is giving the decryption methods to an OSS project). and neither can the bundled SiliconDust software or mobile apps, meaning that my only option was Windows Media Center. This was amusing, as in my 4-5 calls to activate my CableCard, none of the reps I spoke with had ever spoken with someone using Windows Media Center and I had to describe it to them a bit.
Win7 worked for a month until it didn't and wouldn't start working again (bizarrely, even after a machine format), leaving me to spend a weekend hacking WMC into Windows 10 on my DVR. It's definitely off the beaten path, but it works. Hopefully the new SiliconDust DVR software won't suck, because I have a gut feeling my setup will only work until Win7 support ends.
So, tl;dr, the GP can absolutely be right in that his CableCard is decrypting the stream properly, but the broadcast flags are prohibiting him from using an OSS application.