I would venture that there's a huge % of people that either don't care about HD quality picture or don't even watch much TV. Just like the furniture in most RV's, the electronics are mediocre at best.
If you want a nice HD picture then add a BluRay player and sound bar along with a true HD TV. Throw in an inverter to run it when dry camping. If you never dry camp then it's easy to upgrade.
Most soundbars are BT so playing Pandora is easy.
I bet you could do all that for the price of a new Jensen or Furrion.