Google shows a list of Android devices with security patches from last 90 days.

[biron_w]

https://android-developers.googleblog.com/2018/09/android-and-google-play-security.html

HTC only have 2 devices on the list. LG haven't got many and their flagships from last year - G6 and V20 - aren't on there either. Surprisingly Huawei have got a massive list of devices.

 

[biron_w]

It is a shame more Android security patches can't be applied more like older Windows updates though simply installed while in OS and then simple reboot.

That's why Google introduced Project Treble; so security patches can be applied without updating the main software bit. But it still relies on OEMs actually bothering with updates to start with.