The reason it seems steam has stopped using it because it is to volatile atm man! by the time the transfer goes through the price has changed so people are being charged twice in a lot of cases so in till the transactions are quicker or the price has become more stable steam will stay out ^^
Let's be real here, although volatility has been cited it definitely is the smaller issue. The transaction fees are currently too prohibitive for Steam purchases, especially since they strike twice once refunds are considered. At least lightning network seems to be progressing well, it is indeed much needed right now.
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What do you think the largest game platforms stop using Bitcoin?
And how it will affect the Bitcoin acceptance on others services?
I wouldn't be surprised if other services soon follow suit as well, but it won't be because of Steam. I guess Steam is more heavily affected by transaction fees than some of the other services, due to relatively small purchase amounts mixed with a very permissive refund system.