Because swift is a space inefficient language that likes to specialize & copy everything like it's a C++ template, because it's basically C++ templates gone wil

Because swift is a space inefficient language that likes to specialize & copy everything like it's a C++ template, because it's basically C++ templates gone wild under the hood for speed(tm). If you inspect the types swift makes under the hood sometimes, they can get silly huge. Then add codegen for your protobuffer network models and you explain most of the code bloat. 150k lines of objective-c will be significantly smaller than 100k lines of swift pretty much any day of the year. Look at tweetbot for example, still objective c for the most part, a fairly complicated app, still actively developed and only 30MB.