I do not understand how you can still think that after my explanation and after looking at the graph I sent you. One very last try - though I assume in the best case it's for potential other readers.
Go to https://www.computerbase.de/2020-09/samsung-980-pro-ssd-test.... look at the graph. You see that a bunch of them go to the 80C line or hover above. All of them throttle (what you said does not happen). In that graph are shown, going above the limit:
1. FireCuda 520 1TB
2. Patriot Viper VP4100 1TB
3. Samsung 970 Evo 1TB
4. WD Black SN750 1TB (+ the same one with a cooler)
This is only a small part of the market of course, but it goes to show that the throttling is a real thing that happens with multiple models.
Then you had a moving goalpost there, that those SSDs do not throttle under realistic workloads. However, this is a sequential read that's only 5 minutes long. Hardly unrealistic. The hour long constant load benchmark is a different graph, however, constant load is also realistic if it's longer than 5 minutes.
If you activate the other chart modes you see the measured performance, which shows the drops linked to the too high temperature, and that they did the same thing for write performance.
You can counteract this with a lot of targeted airflow and/or a heatsink, the heatsink will at least help move the throttling to a later moment. Gamersnexus had a very impressive demonstration of this, one where they did get this wrong: They had an article about a MSI SSD heatsink where they claimed it did not help (so the SSD did throttle! Again something you said does never happen), where it then turned out that it did not work only because their applied temperature sensors (glued them to the heatsink), and IIRC they also missed the higher performance they got regardless. GN often gets it right, stuff like that happens, but it made this one memorable and highlighted the positive effect of these heatsink coolers.
I'm into this topic professionally for years now. I'm not wrong here. If you can't take my word for it, look at professional SSD reviews, they have covered this also for years now.
And sure: There are scenarios where this does not matter. Gaming. Browsing. But: In those workloads there is no significant difference to a SATA SSD anyway. These NVMe SSDs are only interesting if you have large (and thus: long) file transfers. This is what they have to get right (and some do, but not all of them).
