[kabdib]

Last time I bought some 10Gbit fiber (some AOC, the stuff with SFPs on both ends) it was about $70 for a 3 meter cable. Amortized cost of switch ports are maybe another $200. You paid $700 for a 10Gbit networking card with (say) four ports ... but a LOT more for the server to run all of this.

Back-of-envelope calculation: You can get about 50,000 client connections at 50 updates/sec of 500 bytes each on a 10Gbit link. Four ports, double redundancy gets you 100K clients on a server. Yike -- that's wayyy more clients than you want on a single server (you almost certainly run out of server-side CPU for game simulation and so forth before you run into bandwidth issues). A dual 40Gbit networking card is pretty cheap, but you'll run into CPU load issues trying to feed that card enough traffic -- it's frankly plenty hard to do that even when you're not doing game computation.

You can probably run all of your servers on 1Gbit copper for under $100 / port. There are better ways to wire things up, but I've done this in the past and it's worked fine.

Capital outlay for sufficient server bandwidth just isn't a big deal.

[edit: back-of-envelope calculation low by a factor of 10 :-) ]

[arca_vorago]

70 dollars for 9ft of fiber with connectors? I almost always make my own cables (fiber included) but for some special jobs where it was a time contraint I'd use pre-made but that still seems very steep. Where are you sourcing cables?

I also suppose not everyone knows how to terminate fiber and I've done it so much it's become second nature.

[kabdib]

It might have been closer to $35, I'd have to dig a little. Remember, this is with the SFPs, not just the raw fiber (which is significantly cheaper on its own, even if you buy it terminated).