The smaller speakers in a TV naturally compress the dynamic range because they can't get loud, and especially can't get loud in the lower frequencies that travel more easily through walls. Getting good speakers actually makes the dynamic range problem worse since the loud parts get even louder and travel through walls even easier.
Soundbars have really good margins though, so it's unsurprising that that's the solution they sell!
Soundbars have really good margins though, so it's unsurprising that that's the solution they sell!