This is the best summary I could come up with:

Thirteen Chromebook models have met their death date since June 1 and won't receive security updates or new features from Google anymore.

The US Public Interest Research Group (PIRG) pointed this out in a press release Wednesday, sharing screenshots of the models:

The US PIRG's release highlights eight ChromeOS devices from Asus, Acer, Dell, Lenovo, HP, and Samsung, all easily purchasable on Amazon despite their expirations.

The advocacy group's latest release highlights how easy it is to buy expired laptops, which can lead to security threats, e-waste, and wasted money.

We have been tracking the specific Chromebook models listed in the June letter that recently expired this summer and were shocked to find them still for sale with no warnings.

Retailers need to make changes to protect customers, since Chromebook support expiration dates can be unclear if they're not included on listing pages.

I'm a bot and I'm open source!

You know what's really sick about Google not supporting these legacy Chromebooks?

Schools bought them in bulk for their students. Now they're going to have to do it again. And obviously there is nothing actually wrong with them.

There should be a legal requirement to make documentation available for all unsupported Chromebooks to unlock the boot loader and allow for installing an alternative OS. Furthermore, they should be required to release engineering docs.

I thought they were updated for 8 years.

In other notes, you can apparently install Linux on them ok.

Can't you still load new versions of ChromeOS yourself?

I never liked the "forced upgrade of your OS" anyway. Not for windows or Chrome. It was annoying when ChromeOS kept forcefully insisting I upgrade my Linux when I already had Linux exactly how I wanted it.