

I haven’t heard of that being what threading is, but that threading is about shared resourcing and memory space and not any special relationship with the scheduler.
Per the wiki:
On a multiprocessor or multi-core system, multiple threads can execute in parallel, with every processor or core executing a separate thread simultaneously; on a processor or core with hardware threads, separate software threads can also be executed concurrently by separate hardware threads.
https://en.m.wikipedia.org/wiki/Thread_(computing)
I also think you might be misunderstanding the relationship between concurrency and parallelism; they are not mutually exclusive. Something can be concurrent through parallelism, as the wiki page has (emphasis mine):
Concurrency refers to the ability of a system to execute multiple tasks through simultaneous execution or time-sharing (context switching), sharing resources and managing interactions.
https://en.m.wikipedia.org/wiki/Concurrency_(computer_science)
I don’t know that’s true. The incentives to make it toxic come from engagement being the goal, which is a function of advertising being the income. I’m not advocating for it, but if there were a flat subscription and no ads, I don’t think they’d have any economic pressures for toxicity.