Have never seen any MB OEM 'include' features of newer models, especially PCIe versions. The same would apply with pre-X570 MB's.
That would be like me asking ASRock & ASUS to upgrade my 970 chipset MB's to support PCIe 3.0, which didn't happen. Although both of these OEM's would eventually include 2nd gen (10Gb/sec) NVMe support to some of their latest offerings while waiting on Zen to arrive.
I don't get it, what's there to sue over, false hope? Just sell the current MB & purchase a X570, Newegg is running promos & rebates for some models as of this date. Even the lone mATX offering by ASRock is on promo, along with rebate.
The facts are, these older MB's would be unstable & unsafe by enabling PCIe 4.0 support. Check out the specs of some & one will see why. Most has a fan on the chipset, others has 12-16 pin ATX power connectors versus the usual dual 4 pin. No firmware update can fix the shortcomings of hardware.
However, the one(s) who stated the possibility of PCIe 4.0 support via firmware upgrades should be demoted to a position to where they cannot make statements to the public. That's what this ruckus is about, someone saying it was a possibility. At worst, these comments were an act of stupidity, caused no economic harm to anyone.
As far as comparing this incident to Intel, well they've pulled quite a number of tricks over us, to include not advising Ivy Bridge owners that the IHS wasn't soldered to the die. This would still be largely unknown to many into the Haswell release. It would be writers from tech forums such as this one who exposed the truth over that issue. Later on, it would be someone else (an intern) who uncovered what Intel had swept under the rug years prior, the major security flaws in their CPU's. Sure, AMD also had some, yet nowhere near on the level as Intel.
And still, Gordon Moore hasn't been so much as been indicted by a grand jury for allowing untold millions of those who purchased Intel CPU's with the defects. He will go on to be held unaccountable for Intel's actions under his watch.
This PCIe 4.0 issue is nowhere near on the level as the crimes that Intel has knowingly committed & us end consumers won't receive a cent for our losses.
Lastly, I'm not taking a side, as I've built both AMD & Intel PC's. Although in recent years, due to low pricing, went with AMD 970 series FX-8350/8370 builds. Am looking forward to doing a AMD build, once end of support for the AM4 socket is over sometime in 2020, as they've announced long ago. By then, there'll be another socket altogether, in fact, the 3rd Zen gen may be the last for AM4, as AMD looks to be moving forward faster than Intel these days. Look at long have Intel been promising a 10nm die, while they may have one by now, it's been 4 years in the making. While AMD has released 7nm across most of Zen 3rd gen & being tight lipped over their next move, other than Ryzen 9 3950X due in September of this year.