I would argue that the higher layers of OSI become more abstract and blurry, but it’s not wrong per se. TLS maps fairly well (not perfectly) to presentation layer.

Then again, OSI works best as a descriptive model rather than prescriptive. Plenty of applications don’t follow the model at all. QUIC is largely an optimization by collapsing many functions that OSI models as separate layers into one monolithic thing.

No it's definitely wrong. TLS is not a presentation layer.

> QUIC is largely an optimization by collapsing many functions that OSI models as separate layers into one monolithic thing.

Yeah, or in other words, it doesn't follow the OSI model at all because the OSI model is a relic from the 70s that didn't catch on.