I’ve had precisely the same experience with the NYT that Freddie has:
Me: Here’s a time-sensitive piece, are you interested?
NYT: We like it and will run it, just need a few changes
Me: Here’s the revised version
NYT: …
Me: Hey guys
NYT: …
Me: Hey guys
NYT [when it’s too late for me to place it elsewhere]: Someone on staff is writing a piece along these lines, so we won’t be using yours
Me: You should pay me a kill fee
NYT: We don’t do kill fees. Sucks to be you.
That happened years ago, and I haven’t pitched them anything since. I wouldn’t write for them if they asked me to. They think because they’re the NYT they don’t have to adhere to any of the basic standards of professionalism and courtesy.