Best phones/brands that update the OS regularly / the longest?

I have been with Fi ever since the beginning and I love it, I even have my girlfriend signed up.

I started with a Nexus 6 and no I am using a Pixel XL.

While the Pixel is still going strong, I am enjoying planning my next phone and now that we have more choices I am looking at the various choices.

I plan on keeping my phone for 2-3 years so updates to the OS are important for security and longevity.

Nexus/Pixels are pretty good, but, what about the other brands?

Moto?

Samsung?

LG?

HTC?

HuaWei?

Essential?

Nokia?

OnePlus?

Xiaomi?