What was formally torstatus is officially no longer being run
Since there was not a similar service that I could find, I decided to make a quick replacement
Similar to torstatus.net, every 5 minutes I am checking http://www.swtor.com/server-status
If you're talking about server populations as of the date and time of your post, well, that's likely due to it being decidedly "off-peak" hours, at least for US servers. You won't typically see higher pops that early (6:30AM PST) on weekday mornings. You should see higher pops in the evenings and on weekends. Even then, it's unlikely you'll see higher than "standard" population on any server anymore. But on the most populated servers, you still should be able to find enough people on to group with for ... whatever.
Also, remember, if you see only a very low population on fleet, it may be that there are multiple instances, and the 20 you're seeing is just in your instance. This is especially true if you are "on fleet" but in your guild flagship, as those are a separate instance from the "main" fleet instance.