Something occurs to me when reading most comments. The main concern in my opinion isn't voiced (or I missed it).

Changing old books to match todays standard of correctness means we yearn for a world where ideas are shown to exist and be present far earlier... which means we will show some of today's struggle as "old news" or "already addressed". Changing a book for instance to make it more acceteptive toward LGBT+ means that the issues they faced wasn't that broad and evident.

We should keep older books as they are BECAUSE they can be insensitive. It also should shock us to read some parts, some can be boycotted, but in no way should we change a discourse to match other standards.

They are happy as they forget what unhappiness is (especially as the word will progressively lose its meaning, just like freedom becoming "not physically restrained).

And in the end Winston becomes happy when surrendering. He is broken and ends up being thankful for it (last few sentences of the book)