The solution is use both. They both have their usecases. Cursor's autocomplete and quickly highlight a few lines -> throw into context, plus it's got a very good file index/API (which burns much less tokens than Claude's grep'ing) and whatever else they are doing underneath to optimize it for coding.
Claude is still gold standard if you're not in an IDE though.
Reading files is always the biggest token burning when coding. If it can't find stuff quickly or has to use less and head to trim it before finding it, then you're just wasting context window
Cursor both lets you highlight specific lines multiple times per chat and is much quicker at finding stuff.
Claude is still gold standard if you're not in an IDE though.