you seem to be failing to understand not everyone can accomodate a 65". and i know full well how good large tv's look. my mate has a 75" FALD in his living room which cost £3k from Sony and it has over 1500 zones in it too.
i also own a plasma as well as a XF90 and a 4k LG. I also said in my post he can afford a 65" XF90 and a good sound bar. you seem to be focusing on cheap soundbars. he can afford a YSP 27000 which isn't cheap and will rival home cinema set ups.
you are being extremely biased in your views and using incorrect information. soundbars are now at a point and have been for some time in the high end of the spectrum where they can pretty much do what a 5.1 system can do. they even do atmos too.
again your bias towards size over quality is wrong simply because a 75" edge lit would look terrible. i would much rather have a 65" FALD as would most who know anything about picture quality. OLED also doesn't suit everyones usage. mine especially in 1 of my rooms as it's used purely for static content.
also if you can't understand why people have a big tv and use tv speakers it's down to the fact they don't care. that is a fact 99% of people don't care. the mass market just wants a big tv and they don't care about FALD either or OLED all they want is large for the cheapest price. which is why when they ask me for advice i tell them the tv to buy and then they go to currys and buy the cheapest and largest tv they have on offer like a samsung 6 series.
my mate has a 75" and i would never buy one. he's bought 3 over the past 3 years and he's had to return the first 1 several times due to panel issues. the second again had issues and the third he has kept but it cost £3k. i've seen how it works for him he has a 5 bed house with much larger rooms. i'm in a large detached 3 bed with attached garage. so a 75" would look stupid. 65" is the biggest i will go. so you need to get it in your head there is a limit when it comes to size too and that limit is now been reached for most normal people. FYI my dad has a 5 bed house and bigger tv's than mine and I think they are too small personally as his house is massive.
