why are we including everything in node_modules even when they were never imported before?

Because our default behavior is to search for files which many contain global declarations, like @types/node. This is canonical, and the way to disable it is to specify types: [] (or an actual list of explicit refs) in your tsconfig. We probably shouldn't special-case this, since underscore-prefixed-versioned-libraries-alongside-normal-ones is not what a standard npm environment does, and it can be dealt with via configuration.

this seems rather arbitrary solution.. there has to be a more structured/holistic approach to addressing this problem. i am not sure i understand the behavior of cnpm to be able to have an educated discussion, so i will need to readup and then we can talk.

I think what matters is that there's junk in mode_modules that's automatically included. Not really cnpm specific since there's usually lots of junk in node_modules anyway. See #19893 (comment) from @sheetalkamat

@andy the _rax included in the program is not because everything in node_modules is auto included.. That portion works well wherein when we get base file names for tsconfig.json we wouldnt include node_modules. The file when imports rax it includes the _raxXXXX thing because in the node_modules rax is npm link to that folder... And hence it shows up in the program files.. If you look at the tsserver project files, it wont have any other modules with _ as the prefix. I dont think the current fix is right solution

Replaced by #20395