Hasbro is a bad example in that they have many products. 5e core books are also a bad example because they were created in house when the brand was not doing well at all and staff had been seriously cut. So the traditional best selling book (players handbook) was done when the brand was at a low and no one had a reasonable expectation of the future success of the game.
That is a core issue - to pay staff more you generally have to take a big risk on the profitability of the game. The smaller the publisher the harder this is.
There seems to be pretty stiff resistance once an rpg product reaches a certain price point. I mentioned the AL modules for me. If you look at the reviews of these adventures, they are often mediocre. Raising prices on bad products is doubly hard.
With the current price of shipping from Asia, raising prices may be a direct business need for survival for smaller companies, so we will see.