This is all down to target market.. Target market will dictate how much budget goes into building a car thereby dictating how much the manufacturer sells that model. Truth of the matter is Lexus will not sell you LS600h engineering, spec, attention to detail ,build and ride quality for £22,000 which is roughly how much a CT200h SE fetches neither will BMW sell you 7 series spec, build quality , engineering for 118d money nor Merc sell S class specs and build for A180 CDI money.
What am saying is a Lexus CT will never drive and feel like an LS600h all down to how much it initially cost to build the 600h compared to the 200h. book a test drive at BMW/ Merc dealership for both their S Class and 7 series models then right after hop into their 118d and A180 CDI models respectively and you will notice a very big difference as to how the S Class and 7 series goes about things on the road and the whole ambience compared to 118d and A180 CDI models. I personally experienced this when I test drove both a GS300 and IS300 when I was looking for a Lexus and could immedialtely tell more enginnering and quality went into the GS compared to the IS and went for the IS due to its handling compared to the coushin feeling GS. my previous 520i BMW also rides better than my mates 330Ci model but 330 handles better and more agile compared to the 5 series.
Lexus can build a CT200h and give it attention to details and build and ride quality just like the LS600h model but you will have to be willing and ready to at least pay around double of how much the CT's currently fetch now at the showrooms. same will apply when you walk into BMW, Merc or Audi dealerships.
So is a CT200h a 'real' Lexus? my answer will be yes it certainly is as its real purpose was to offer the driver an 'entry level' model into the Lexus brand, a quiet/refinement drive from its hybrid technology whilst returning around 70mpg during the process at a price tag of around £20,000 but for the LS experience, build quality and attention to detail, one should be willing to pay around £60,000 + for that.