Realistically, 1gbit connection is good for uploading and downloading huge architectural plans, but other than that, I rarely use anything close to it's max capacity. It's like having a killer sports car that will go 0 to 60 in a few seconds, but you rarely have the need to do that.

10gbit fiber locally doesn't mean I have this speed to the internet (I'm not).

It's a trade off. Buy older equipment and DDR3 is cheap. I dropped 40 more gb on the server for about $45 USD. The downside is that older equipment is not as energy efficient and as fast as newer equipment.