So the company gain in two ways for accepting bitcoin for payments and if the price of bitcoin goes upward interest are generated also.
Well you did said about volatile so that's one of the reason why some of the big companies or even the smaller ones are not gonna accepting bitcoin as their payment because of how volatile the market is and it could either make the company profit of their bitcoins or things will go in the opposite way. The other reason is transaction fee but it's not a big deal.
Steam was accepting Bitcoin for quite some time but unfortunately they removed it:
https://hexus.net/business/news/internet/112973-valve-removes-bitcoin-payment-option-steam/Well, bitcoin's biggest problem lies only in the fees. however, it seems that almost everyone has accepted it in their business. So far, not only bitcoin, but ethereum and even BNB have also become one of the payment recommendations for businesses, especially BNB because of low fees and fast transactions.
however, this goes back to the regulations in their respective countries. there are so many advantages to adopting bitcoin or other crypto in the business world.
I think steam is just not ready for the fluctuations that exist in bitcoin.