Skylake works with win7, kaby lake isn't officially supported. Whether microsoft sticks with win10 indefinitely with updates or comes out with a new product, at some point win7 will become obsolete. There's little chance of running win7 "forever" just because tech, software, platforms continue to move forward. Eventually it means older os's won't have the necessary security or support for various hardware or even software such as browsers.
It will reach a point where websites begin using a newer version of flash or html6 or 7 (or some other future designation) that flat isn't supported by an older browser and only supported by current browsers (in the future) which have software support the older versions don't. Eventually sites like youtube or others may not work at all with older software limited by older os's and hardware.
Some may consider it a 'trick' by MS though eventually things move forward and a line has to be drawn somewhere. Where to cut off legacy (old) support and make room for the current and future tech. Legacy support can hold back innovation and/or cause conflicts or bloat an operating system. I've not tried personally but imagine there would be a real issue trying to load windows 7 onto something old like an intel 8086 cpu. It doesn't mean MS is pulling some kind of 'trick', it means the 8086 is old and it would be too difficult trying to support every piece of hardware under the sun.
As much as I like win7 the fact is it's nearly 8yrs old. In the tech industry that's a long time and you can only patch things so much before it makes sense to just build something new from the ground up so it's leaner, more efficient and current. For the same reason people use chrome or firefox instead of netscape 3.0.