Buildings are obviously worse than trees, but trees certainly do attenuate, maybe not as much as you would think though.
I have experimented quite a bit with antenna placement, dense trees and attenuation, reflections etc. I have quite the tree lab around my station and figured out which trees are worse (long needle pines, especially when wet). My worst attenuation is north and west/sw (the directions in the photos below).
It’s not so bad for me since most traffic coming my way is from south and east. But in those directions I have up to 14,000 foot mountains… I do get roughly heywhatsthat range east and southeast to the mountains… (antenna is outside, 30 feet up, tucked inside a tree, I’m at 500 ft elevation which helps).
My indoor range was very short. The best results for me came from moving outside with FA antenna or DPD antenna and AirSpy + Uputronics LNA with a higher AirSpy gain that I would have thought. You may benefit from AirSpy with increased dynamic range at higher gain to compensate for attenuation.