Earlier quoted context omitted.
So what does the ending mean then?
He made it all the way to Jupiter, and figured he might as well check out the monolith despite the disaster of the mission so far. He took the pod to check it out. He was then taken through a portal in the monolith to the home system of the aliens that created the monolith. There, he was put in a simulation as best as could be created based on TV signals from earth. The simulation was of a hotel room in a particular…
"Without consulting or confronting his co-creator, Kubrick cut a huge amount of Arthur’s voice-over explanation during the final edit... As it turned out, Arthur did not get to see the completed film until the US private premiere. He was shocked by the transformation. Almost every element of explanation had been removed. Reams of voice-over narration had been cut. Far from being a pseudo-documentary, the film was now elusive, ambiguous and thoroughly unclear. Close to tears, he left at the intermission..."
(full article: https://www.newstatesman.com/culture/2017/01/close-tears-he-...)