I bet you love Being There, the most boring, least funny Sellers movie.
Every day's a new adventure.

This may be my least favorite Sellers movie.
Stupid, not silly.
Embarrassing situations abound, with absurd reactions from the various characters.
Whatever.

To appreciate this (which I happen to, and it's become a new year's eve tradition with my Mom), it takes a willingness to suspend belief and logic. This movie is
SILLY
. I love it for that reason, but I understand it's not to everyone's taste.
It, for me anyway, also plays on a fantasy of living in, or at least visiting, a very rich house, with just about anything you could want, i.e. their current top-of-the-line gadgetry. That sunken living room with its round fireplace is just too groovy for words.
My suggestion is watch it with a group of friends, set out the people num nums, and join the party in real time. Pretty soon I think you'll start having fun.
Don't worry about how realistic it isn't, or that it's vacuous. Just share it and you may find yourself quoting stuff I really look forward to seeing it every year with my Mom. It's ridiculous and the characters are all koo koo (even the snobby lady who doesn't speak Hindustani) ..

The formalism is part of what makes the film great. You'd probably hate Tati's Playtime too.

I mostly agree with you on this. There is no real story, and certainly no moral to the story. The plot revolves around a bumbling foreigner trying to fit in at an exclusive Hollywood partyand that's about it. The rest of the movie is just the ridiculous situations he either creates, or finds himself in. And that could be all you need, if there were enough funny situations or dialogue to go along with it. Sometimes you don't need more than that (Seinfeld was famous for being about 'nothing' too). But this is the second part on which I agree - I was genuinely surprised about how unfunny this movie was at times.
Don't get me wrong, there were some funny parts for sure, the bathroom fail maybe the best of them. There were a few other memorable scenes, and Hrundi's sad attempts to fit in (like with the cowboy) were kind of funny. But the ending really fell off the cliff for me. It seems like fifteen minutes or more devoted to a bunch of kids bringing a painted elephant to a party? And then the commotion that ensued when it was decided to wash the elephant of the paint it was covered in? Umok? I'm not sure what that was, but it wasn't funny, it was boring, I agree. It just kept dragging on. OK the house is filled with foam.sorry that just fell seriously flat. At least if things happened to make me laugh, I wouldn't have questioned where the story was going. But nothing happened to make me laugh. Just a lot of expanding foam and Mrs. Clutterbuck falling into the foam twice and that's about it. The film just died a slow death there IMO.

but every movie in which a story is needed needs a story and this movie doesn't have one.

Ultimately it's just "boy gets girl". Gags don't need much story to justify their use!
"All necessary truth is its own evidence." - Ralph Waldo Emerson

then explain to me the story of the party? I mean you have to have some story, something happening to keep viewers interested. and nothing ever happens in this movie. it's just random, and meaningless comedy vignettes. it might as well be a sketch comedy show sketches.

Well, comedies of this sort don't need much of a story, just a series of situations. Buster Keaton made this point in his autobiography in an anecdote involving a film he wanted to do when he was at MGM but Irving Thalberg rejected it due to its not having a good story. He couldn't get Thalberg to understand that the film didn't need as much of a plot as he was insisting on. That's the kind of comedy THE PARTY tries to be.
"All necessary truth is its own evidence." - Ralph Waldo Emerson

watching things unfold at their own pace? how about nothing ever happens? the movie is about nothing. it's just a mishmash of shenanigans which don't lead to anything happening. it doesn't have a story.

I own it on DVD and have seen it many times. When it first came out, I went to see it several times during its run. But I have to admit that there are times I see it as very clever and well-played and other times it seems slow and not very funny. It's most enjoyed, for me at least, watching with someone and in a laid-back mood where you're not wanting the story to get on with it but just don't mind watching things unfold at their own pace. It's one of those films that seems to have as many people who love it as hate it.
"All necessary truth is its own evidence." - Ralph Waldo Emerson