Why is Latitude e6530 discontinued from Windows 10 feasibility testing ?

I am experiencing DPC latency, which can be remedied by switching off the (internal) Intel (R) 82957LM Gigabit network adaptor. That is nice, but instead I'd rather try my luck with an update of the driver software. Although I have dutifully installed every system update once it became available from either Windows by Microsoft or Dell, this latencey keeps bugging me.

After discussions with Intel Customer Support, I once more tried my luck with Dell and found that the recent- most driver for this appliance was v12.12.140.22, which was offered and installed on July 23, 2015

After digging deeper in the "Why and How", I found on the Dell Support site that the last Windows10 update that showed a feasibility check for the Dell Latitude e6xxx models, was Win 10's Fall Creators Update 2017, aka build1709 .... Consequently and as stated by Dell theirselves : "If your computer model is not listed, the hardware is not tested by Dell and drivers are not updated for that model." (Support > Knowledge Base, page in Dutch, with reference number 000180684).

Why has Dell discontinued support of their Latitude e6xxx range?  To this day, all other Latitudes are still supported, so I don't expect life cycle to be an issue. Although I bought it new in 2012, it is a sturdy and reliable workhorse to me and it still serves me well.

Is there anyone who can give me the gist of this? Your answer will be much appreciated. (By the way: don't offer me a USB network adapter as a work-around.)