Most of these features have a function that is an important improvement to the function of the flashlight.
Trapezoidal Threads - increase thread smoothness, strength, and longevity/lifespan
Double-AR Coated Sapphire Crystal Lens - increases light transmission(brightness) and increases scratch resistance which keeps the transmission high
Gold Plated Electrical Contacts - increases efficiency and runtimes
Pushbutton Tailswitch - pretty standard feature
You have to realize that there is a heck of a lot more to light quality then CRI right? There is tint(distance from black body radiation line), tint shift or lack there of, colour temperature, reflector design(geometry/efficiency), lens efficiency/light transmission/longevity, driver regulation, emitter size/design/efficiency, etc. CRI is also one of the worst measurement systems of a lights ability to render colours and only takes into account a small sample of the colour palette. You can have a light with a very high CRI that is actually terrible at rendering certain colours. I generally try and shoot for lights with a higher CRI if available as well but, CRI is only a small part of the equation and still only a rough guide. If you let it be the sole deciding factor on your light purchases, you could end up missing out on some pretty nice lights.
Remember too that there are many other considerations when deciding on a light. A light with 98 CRI but, is only 22 lumens, has a runtime of 46 seconds, is made of 5052 aluminum painted with rust paint, and is turned on with a toggle switch would still be a pretty crappy light