We are sued.
Better not risk it.
Also Gamers are the walking definition of a hostile customer. Give them no quarter to call you incompetent.
(also, we are talking enormous binary blobs, not easy to recover from if partially written- most databases don't store large rows in-line for performance reasons)
One of the 10.6 versions had (has?) a bug where a connection sometimes simply does not die ever, even after disconnecting and killing the query using the KILL sql command, so it never releases its slot (which matters if you have lots of connections), although to be fair I've only hit that once since we upgraded to 10.6.
Frankly I prefer MySQL and friends over Postgres simply because that's what I always used and I find it familiar (plus I don't like the process based concurrency that Postgres has, while I haven't really tried it to see if it matters, process creation is fairly expensive in Windows to use as a concurrency mechanism and limits the numbers of connections a lot more than threads), but let's not deny reality here, MySQL has never been rock-solid and a glance at its source code should be enough to tell you why.
As for your disregard for performance issues, it's hard to say if it's warranted without knowing the numbers and the load profile but it's probably preferable to spend the time to test it properly than having to fix everything in a hurry later with customers screaming at you over the phone.
Plus I like programs built to be snappy and fast, a good practice that sadly has been lost to time.
Putting aside that you seem to criticize that premise instead of the system development approach that fulfills the premise, I suspect that the resulting mess of support requests, manual intervention, and community unrest Ubisoft (or any other MMORPG developer) would find themselves in, if, say, "the shiny sword of atrocious doom" that players spent 240 hours sinking their life into obtaining were to disappear regularly, is probably not worth it.
I understand this despite not doing any online gaming myself.
I wouldn't run around cursing their name but I would probably stop playing for a period of time. Whether or not that's a problem depends on their business model.