Yep. I've lost a couple of characters in D&D 2024 games and more in earlier D&D. The options to retreat often aren't amazing, with attacks of opportunity and opponents often having superior movement. Furthermore characters that are willing to just abandon their comrades early in the fight are relatively rare IME.
The first character death of mine was a near-TPK (one party member survived). Assuming that the DM hadn't overtuned the encounter, the monsters just got lucky and dealt out more damage than the party could sustain. We were guarding a refugee caravan at the time and none of the group was playing the sort of poltroon who would just run and let them get massacred.
The second was where the party were raising a temple to disrupt a ritual and rescue a prisoner/sacrifice. We got in with a certain amount of stealth, but when a fight kicked off we stayed together rather than scattering in a manner that might have allowed an individual to desert the fight and escape. While were were able to support each other better, when people started to go down, it created a fairly rapid death spiral.
I was careful to avoid absolutes, so what are the playstyles where TPKs are advantageous that you believe I was excluding?
Even a high-mortality game runs better when there is continuity throughout the party as it advances through the plot, even if it is in a "ship of Theseus" fashion.
In contrast, after a TPK, assuming the group doesn't just abandon the as-yet-unplayed plot that the DM has created, the new party will need to have their characters ignorant of all the information that their predecessors had discovered and investigate the same things that their previous characters already had. The DM will also have to recreate the motivation that the previous party had already built up to actually follow and resolve the plot.