I believe this to be a utility issue. In the average home network, having greater than a gig networking provides little value for the center of the bell curve of users.

Maybe its different outside of America but most people in America have less than 1gbps internet connections, and have little need to transfer data in-house from one location to another that the time saved by having a 5, 10, or 25gbps connection would benefit them in any measurable way.

Even for those people who run NAS systems for extra storage will only saturate gigabit connections occasionally, and being able to save a few hours a year waiting for transfers to complete is likely not worth the initial setup effort and costs for them.

I'm a bit of a techie, and my house is wired for 10gbps internally, but no isp in my area offers more than 1gbps, and I live in a well-to-do and densely populated area near to many tech companies.

So, in short, 1gbps is not obsolete. It probably should be, but it still meets the needs of the great majority of people that use it.