Heh, I once found a "feature" in a kernel driver in my Xperia (with a SoC from the company with a name starting in M) that allowed you to read arbitrary kernel memory from userspace, by passing the appropriate structures via a ioctl interface. Didn't even have to dig around too much.
Ah well, at least I got a t-shirt from Sony.
Anyway, the issue is fixed in recent firmware versions.
When questioned about this on the Android Platform 11 AMA last month, they stated that they think OEMs freedom is what makes Android a rich ecosystem.
So there you have it. Can check by yourself on Reddit.
However not forcing OEMs to provide updates, even with Project Mainline and GSI now as Treble updates, doesn't change anything from consumer point of view.
My older OnePlus 3 got updates for almost 4 years I think. Not bad, but it's not like apple's 5-6 years. Still, it was half the price of an iPhone with better hardware to boot so fair trade I guess.
I don't like frivolous spending on phones but I never keep a phone more than 4 years anyway. The progress of camera, microphone and speaker quality alone across 4 years is enough of a quality of life improvement for me to upgrade.
At this rate of Android security issues, my next phone will probably be the next iPhone SE but only if they update the display to a larger 1080p 90Hz panel and add an ultrawide camera lens, I don't care about anything else.
And that's only the Qualcomm stuff. There is another CPU vendor beginning with M who is big in el-cheapo hardware - look at their Android kernel leaks, wherever you dig you find horrid, HORRID code.
Google should mandate full open source disclosure of all GPL'd components as part of the Play Store certification and unlockable bootloaders, otherwise this shit is never going to change.