'ego-death and dimensional transcendence' and 'lots of paranoia and distress' just sound like different framings of what could be remarkably similar psychic states.

Having been in both, they are worlds apart. Sure, those descriptors might be tossed around, but that's a short commming of English to properly convey experiences.

Its distressing to spill your coffee. It's also distressing to have your house burn down. The difference is large.

Nothing wrong with experiences like what are called ego-death and dimensional transcendence if it doesn't involve paranoia or distress. Especially with dissociatives these are often the goal, and are quite pleasant.

The THC induced paranoia and distress are usually due to effects like time-dilation, memory impairment, depersonalization, thought loops etc, which I'd put into more or less same category as you get from psychedelics or dissociatives.

Plenty of bad trips with quite low doses of THC too: https://erowid.org/experiences/exp.php?ID=70884

I think the "hardness" of different drugs, especially in how strong the effect is, is mostly a cultural and legal artifact that doesn't really correlate that much with the actual experience.