You're right, with no comparison I may be happy, but it would irk me something rotten if I later found out it WAS an IPS panel and therefore I wasn't getting blacks as good, plus with RGBW the image would definitely be worse. I'd gladly pay a bit more for better... a Samsung or Hisense which I know have VA panels and no RGBW. It's just principle alone... I want to know what I'm paying for.
VA is well loved by professional reviews and high end TV buyers because it's well suited to TV watching in a home theatre environment.
IPS is popular in the mid-range because VA loses many of it's advantages in a less dedicated room. Having the lights on reduces the gap between contrast ratios and having the TV in a convenient place for the plug and furniture rather than carefully positioned also reduced the contrast difference.
IPS isn't a cheaper version. In other fields IPS is the only display technology used in the high end. If you pay two or three thousand pounds for an image editing monitor it'll be IPS. Ditto the £5k your hospital paid for it's medical imaging screens that doctors used to diagnose X-ray and scan results.
It's just a different set of trade-offs.
As for RGBW, LG have seen that 4K is too much resoution for the typical size and viewing distance. They've removed the colour filter from some of those extra pixels making the display more power efficient without impacting on the perceived detail for most of their buyers. It may even have reduced the cost too.
If it was a flagship display you'd be rightly miffed, but on a mid-range display everything is a couple of steps down from what the technology can do. I wouldn't be bothered about the compromise made in any particular element unless it has a disproportionate impact on what you're doing. It's all about which TV's set of compromises together produce the best picture.
The line between something that actually annoys you and something you're happy with but might have been better is difficult one to find. As long as you end up on the right side of that line then there are more interesting things to do than worry about maybes.