When was the hypothesis for the supposed existence published?

1950?

That's almost 60 years ago.

Ignoring the countless number of baseball or beachball sized chunks of dirty ice,
the Oort Cloud was [according to theory] supposed to be teaming with millions and billions and trillions
of chunks of dirty ice ranging from the size of houses to the size of large countries ALL orbiting way out there
beyond Pluto in an all encircling 'cloud' around our Solar System.

In the FAR [liquid helium temperatures] or MID-INFRARED ][LOX temperatures], those millions and billions and triillions of huge chunks and bodies of
ice should glitter like countless [but admittedly faint] diamonds every direction we point our FAR or MID-INFRARED cameras and telescopes, whether onboard satellites like IRAS [launched in 1983] or onboard NASA high-altitude aircraft.

So?
Where's the VISUAL evidence for the cloud's existence?

What do I say?...I say, the Emperor Has No Clothes!!

All those astronomers and astrophysicists who fell in love with the Oort Cloud theory have been in essence
saying [PROVERBIALLY] that the Emperor is wearing his finest clothes, so we should accept that....
But...it's time to take the blinding conformist scales off our intellectual eyes and realize that those
scientists have deluded themselves; the Emperor is actually naked!

Yes, Nick!...It's not a politically-correct thing to say, but REGARDLESS!....Pulling no punches, I REITTERATE!!....
Those freakin' scientists had deluded themselves about that theory.

What about Sedna and those other bodies found way out there?

What about them? I could could count them on my fingers....And they apparently belong to the Kuiper Belt.

WAIT!...You may say...We don't have imaging systems powerful enough to detect the Oort ice chunks smaller than a city.
And we hAaven't really looked long enough over 60 years.

I agree that back in 1950, the most powerful scope was the 200 inch Mt. Palomar
and there were no orbiting INFRARED observatories in space back then.

BUT THINGS HAVE CHANGED!!!...Since the 1970'S there have been MID & FAR INFRARED telescopes [with mirrors at least 30 cm] carried aloft by aircraft
and balloons...And since 1983, there have been several such INFRARED telescopes placed in orbit....And then there are those IR telescopes with enormous
mirrors and IR photon capturing capability on top of a Hawaiian mountain

And?

And how many 1,000s or millions of large [mythical] Oort Cloud bodies have been imaged in the FAR or MID-INFRARED?

Answer: "O", Zilch, Zippo, Nada, Zero.

The Oort Cloud is a myth!!!