1a. (original) Winston said he had noticed a continued decrease in his suicidal ideation.
1b. (simplified) Winston noticed a decrease in his suicidal ideation.
2. Winston's suicidal ideation decreased.
3. There was a decrease in the suicidal ideation Winston felt.
4. Suicidal ideation decreased in the patient.
Many more syntactic repackagings of similar propositional content are possible, too. For perfect recall, rule-based systems need to grapple with this, and additionally, in a real setting you're probably getting predicted (rather than gold-standard) POS tags, relations, etc., adding additional noise.
My expectation (as someone who's mildly bearish on LLMs, btw) would be that if an LLM appears to be doing worse than a rule-based system then you probably haven't tried some low-hanging fruit yet such as adjusting prompting strategies, fine-tuning, using different pretraining data, etc.
In 1a, someone says something. In 4, you seem to have an objective fact about a patient.