Was the “bank prop trader” ever real, or mostly a myth?

I’ve been reading pre-2008 financial statements from major banks (GS, JPM, MS, UBS) to understand what “the trader” actually looked like before the Volcker Rule. One thing that stands out is how difficult it is to isolate any clean “proprietary trading” number or assess its returns.

Disclosures are typically at the segment level (FICC trading revenue, equities trading revenue, and occasionally “principal investments”), which makes it hard to draw firm conclusions. Banks clearly state they engage in proprietary trading, but it’s never broken out explicitly-it seems embedded within broader activities like market-making, client facilitation, and structured positions.

So my question is: did the stereotypical “bank prop trader” actually exist in a meaningful way? By that I mean a relatively standalone, PnL-driven trader-not someone primarily executing or facilitating client trades. Or is that mostly a simplification or pop-culture artifact that never really existed in that form?