I don't know about other countries' armies, but in the US Army, use of these sort of platforms in trees is discouraged. As one of my Platoon Leaders, 2LT Brian Earl, said, "They are good die-in-place spots."

There a picture in WW2 of an Australian soldier with a bren gun literally chopping a palm tree to bits to deal with a sniper.
Not much maneuverability when you're stuck up in a tree

The Japanese had a very different mindset though. They'd leave stay-behind guys literally roped into the tree tops. They weren't expected to survive very long, just take out a bunch of the enemy before death.

The Viet Cong had an "elite" group during the Vietnam War, called "Death Commandos." It's members were chained to trees in the face of an unstoppable US advance or to cover a withdrawal, and they were given hoards of ammo and usually a high-ROF, decent caliber weapon like an RPD, and just kept firing at any enemy troops they could see and kill as many of them as possible before they were killed. They were effective, but there were never many of them (I guess the VC were not insane either).

All my 1960s work has got me casting back a few decades, but one of the scenarios I've been working on involves unexploded M55 rockets...

https://fas.org/man/dod-101/sys/land/m55.htm
http://ye-old-stompin-ground.com/pla...0Launcher.html