The 4900 HS is actually a 35 watt chip.... Linus makes a mistake in the video you linked saying its 45watts (early into it).
I think he made a mistake, thinking of the TPD of the intel chip.
The Core i7-9750H hes compairing the 4900 HS against, is a 45watt chip.
So basically AMD has a 35watt chip thats beat the current 45watt chip of intels, in laptops.