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When Baldur's Gate 3 came out, Steam's overall bandwidth consumption went from around 18 Tbps to 146 Tbps
(reddthat.com)
From Steam's self-published stats.
Baldur's Gate 3 could not be preloaded and weighed in at 125 gigabytes on disk, so when the game left Early Access at 11am US Eastern yesterday, Steam's bandwidth utilization shot up 8x over a span of 30 minutes. I know personally, I saw my download hit over 600 Mbps across a 1 Gbps fiber connection.
Kudos to the system engineers at Valve. It is mind-boggling that they have built infrastructure that robust.
Yeah you can get some nippy ones these days, faster than an HDD so arguably suitable to run off of. Only thing I've noticed is that fast USB sticks can saturate a pair of ports on a lot of devices - if you have, say, a mouse in the other port then the movement might get stuttery when transferring at full pace.