Q:

Unblock template and media in Robots TXT for Google Webmaster Tools?

I've been working a lot with SEO for clients lately and I've noted that they are requiring access to the template in Webmaster Tools now to establish that a site is mobile-friendly.  
Google is ranking sites lower when CSS and js for the template is blocked.  The current default robots txt blocks those folders.
Is there any negative result of unblocking the /templates and /media/system folders via the robots txt?  I assume they were put there for a reason, but it looks like in Github some of the development versions don't include those folders.
What's the pro and con on that?

A:

In my experience there is some time you need to open and sometimes needs to block  /templates and /media/system in robots.txt (Its based on your site too)
Type 1
Normal sites not much JS/CSS controlling your layouts!
The basic idea of Joomla is rendering everything through index.php so there no situation to access these files directly in above folders (only on print template or custom 404 based on your configurations).so better to block it.

Google is ranking sites lower when CSS and js for the template is
  blocked

I wonder and not sure this is the real problem, Bcoz we have many sites that blocked this folders and have good ranking. I think this is something else may be related to loading speed.
Optimize the site using Google page speed test then it should be much better.
Type 2
There is a situation like low rank due to these folders blocking its mostly based on the site behavior, like some new trends SPA,responsive etc will effect these folders.
You can get more information from here  and here.
So its up-to you based on your site type you can open it or block it.
Hope it helps.

