Sometimes, yes. A poor translation can absolutely ruin it. I'd love to learn ancient Greek for the sole purpose of being able to read the poetry.

I agree to an extent, but not all translations are equal and you can research how they were translated pretty easily. W. G. Sebald was involved with the German to English translation of all his books and they turned out fantastic (I don't have any idea what the German versions are like though).

I've read a lot of books in two, sometimes three languages and something very essential is always lost.
The only exception might be Nabokov's Russian translation of Lolita, but that's because he's a singular genius with both languages.

I'm quite fond of Robert Pinsky lately:

… our language, forged in the dark by centuries of violent
pressure, underground, out of the stuff of dead life.

Thirsty and languorous after their long black sleep
The old gods crooned and shuffled and shook their heads.
Dry, dry. By railroad they set out
Across the desert of stars to drink the world
Our mouths had soaked
In the strange sentences we made
While they were asleep: a pollen-tinted
Slurry of passion and lapsed
Intention, whose imagined
Taste made the savage deities hiss and snort.

In the lightless carriages, a smell of snake
And coarse fur, glands of lymphless breath
And ichor, the avid stenches of
Immortal bodies.

Their long train clicked and sighed
Through the gulfs of night between the planets
And came down through the evening fog
Of redwood canyons. From the train
At sunset, fiery warehouse windows
Along a wharf. Then dusk, a gash of neon:
Bar. Black pinewoods, a junction crossing, glimpses
Of sluggish surf among the rocks, a moan
Of dreamy forgotten divinity calling and fading
Against the windows of a town. Inside
The train, a flash
Of dragonfly wings, an antlered brow.

Black night again, and then
After the bridge, a palace on the water:

The great Refinery-impossible city of lights,
A million bulbs tracing its turreted
Boulevards and mazes. The castle of a person
Pronounced alive, the Corporation: a fictional
Lord real in law.

Barbicans and torches
Along the siding where the engine slows
At the central tanks, a ward
Of steel palisades, valved and chandeliered.

The muttering gods
Greedily penetrate those bright pavilions-
Libation of Benzene, Naphthalene, Asphalt,
Gasoline, Tar: syllables
Fractioned and cracked from unarticulated

Crude, the smeared keep of life that fed
On itself in pitchy darkness when the gods
Were new-inedible, volatile
And sublimated afresh to sting
Our tongues who use it, refined from oil of stone.

The gods batten on the vats, and drink up
Lovecries and memorized Chaucer, lines from movies
And songs hoarded in mortmain: exiles’ charms,
The basal or desperate distillates of breath
Steeped, brewed and spent
As though we were their aphids, or their bees,
That monstered up sweetness for them while they dozed.

^That's interesting, but does it count as poetry?

I want to say yes.

po·et·ry
ˈpōətrē/
noun
literary work in which special intensity is given to the expression of feelings and ideas by the use of distinctive style and rhythm; poems collectively or as a genre of literature.

It's got distinctive style out the ass at the very least.

Found these C.K. Williams poetry fragments on my computer (each is from a different poem, though they go oddly well together) :

https://s10.postimg.org/f5ifpn7ex/ck-downwards.png

https://s29.postimg.org/voj80d0ev/ck-symbols-dog.png

https://s16.postimg.org/55t4ul1b9/ck-storm.png