Why the television manufacturers (Samsung, Sony, LG, so on) exceed the voltage capacity on led strips (backlight) on TV's?
Isn't 133V the open-circuit voltage? When LEDs are working, voltage should be lower.

LEDs are driven by constant current sources, it's far better than using voltage regulation, because LEDs have widely varying forward voltages and they tend to have negative temperature coefficient :
Overheating reduces voltage which raises current with a constant voltage regulator which leads to even more overheating until one LED in the chain die.

Here is for example the datasheet of a LED driver used in a LG TV I've repaired :

https://fscdn.rohm.com/en/products/databook/datasheet/ic/power/led_driver/bd9285f-e.pdf

"Current mode DCDC converter"