Fwiw, Sony's current mid-to-high end a7 line of mirrorless cameras (eg: the a7 IV) don't have this video recording limit. They also handle long recordings fine assuming it's on a tripod and screen is in the flipped out position[1] (the link ran a capture at 4K/60fps for 3 hours before ending the test arbitrarily).

[1] @2:50 https://www.youtube.com/watch?v=d9GHftTU7fE

$5000 DSLRs have huge APSC/Full frame sensors to try and cool... try and take a bulb mode shot on one and let me know if they let you past 30 minutes.