I'd prefer maintaining a 10k LoC python project rather than a 10k LoC Java project (which would likely be 8k lines of boilerplate anyway)
The ease and safety you can make huge refactors is a huge win. Sure you can do it in python, but you will be writing x10 the amount of tests and final LOC counts including tests will probably have python come in closer to Java than the 10k > 100k loc indicates