I see your point here, but I still think honking is good. In dense environments—cities as you say—honking should be reserved for emergencies, which Philadelphia was one. Density and necessity of honks are both on a spectrum; one should take both into account.
The anecdote about my first time driving in a city was not to excuse my poor judgment and recommend noobs rely on being honked to improve their judgement. I have, since, not made such mistakes ever again, including on the way back that day, but it was impossible to judge my unpreparedness accurately before actually trying it. (After all, I did pass the driving test smoothly.) Thus, insofar as some drivers will be bad sometimes, honking at them helps, because they know they’re bad but they probably don’t know when they’re particularly screwing up.
The other point about honking not conveying enough bits of information is true but what are the alternatives short of speaking to them (often not an option) or bumping into them (not good)? I’ve seen people flashing their headlights but that’s circumstantial (night, heading your way).
This makes me think of the Cooperative Principles, per Grice’s maxims, which is a concept in linguistics, pragmatics specifically. Coming from linguistics, I separate concepts of semantics (what a sentence means), pragmatics (what a sentence means in context that you can infer from a transcript), and paralinguistics (what one conveys at large in an instance where language is used, but also possibly related to gesturing, body positions, facial expressions...)
For me, lying is a concept that applies to semantics only.
Failing the cooperative principles means failing to be cooperative in communication, which is a superset of lying.