RG-59 is still used because its cheap and the average new home customer cant tell that its RG-59 when they have been charged for RG-6. Most apartment buildings up until 10 years ago were wired with 59, but with cable companies like comcast getting on the scene even before ground is broken they have landed contracts to be the sole provider of cable tv service and generaly do the wiring of the complex.
Aparment installs are a majour pain in the ass because grounding is the first issue and second issue is the rules that most complex management has for the install. Most only allow for a non secured mount such as a cement filled bucket, a patio paver, or a tripod. Second they generaly dont allow for any wall or window frame penetrations so your left with using flat cable or some funky contraption involving furing strips and luck.
Using rg-59 regardless of what receiver type is a gamble, it may work for 10 years or 10 seconds and its best to just not use it at all.
If you use the flat cable correctly and put some effort into it it doesnt look bad at all, I did a couble were I used double sided tape to use the flat cable to cap the end of the non moving doorwall section and then secure the coax to both sides.