I would say default cap that could be changed would be the best option. Since vsync often gets modified by global control panel options and the new fancy "uncapped" options such as we see with gsync/freesync and fast sync. Besides, there is no need to worry about input lag in a title like this where someone would have a real need to play unlimited.
As for why it only happens for some, I think you need high enough specifications to create a situation where the card is spitting out high FPS. I've got a 3080 Holo amp with a lower voltage mod, and custom repaste, new thermal pads, and 3X noctua A9. Then a 5600x CPU at stock.
With things like CSGO and other games that could run-away fry a GPU, it was always the systems that over-performed. That's only a fraction of the market. Of that fraction, only a few are likely to be actively monitoring their PC temperatures.
You must be registered to see the links
So like a 3080 is only 1% of users, roughly. Creating that rare "one off" situation in the feedback.