From Wiktionary, the free dictionary
Ironic inversion of go hard.
go soft (third-person singular simple present goes soft, present participle going soft, simple past went soft, past participle gone soft)
- (intransitive, stative, slang, ironic) To be mediocre or not particularly excellent.
- Antonym: go hard
Goes kinda soft tbh.
- Used other than figuratively or idiomatically: see go, soft. Literally, “to become soft”.