Practically speaking, the bigger issue is going to be that you don't have wires going to where you want them. Cat 5e supports gigabit speed and was became the standard in 2001. Practically speaking, many cat5 cables from before than happen to work well enough to be used as if they were cat5e (particularly if you don't push the distance), which pushes the date back to 1995.
A lot of equipment you can buy today still only goes up to 100Mb/s, and a lot of houses still don't get even that from their ISPs.
Even if you have a gigabit connection, most of the time the computer at the other end isn't going to be sending you data at gigabit speed.
You might want gigabit speed to support multiple devices. But most houses don't have that many devices consuming high bandwidth at once, and when they do, you can feed them with multiple wires and/or access points.
All of this is to say, for almost every house, the standard cable from 1995 is still perfectly adequate. Cat5e will probably still be fine, by the time you sell your house.
Wifi tends to have issues with packet drop. Not an issue for YouTube, but in online gaming this matters.
Another issue is in high density situations, like in apartment buildings where everyone has their own wifi, or typical flats or condos in European cities. There just aren't that many wifi channels, and if you have multiple people on the same channel say goodbye to your speed
Because when you have 8 devices, all 8 devices are sharing that 100MB connection.
And you really have like 25 devices on the 2.4Ghz spectrum, because your neighbors exist and everyone maxes out their WiFi router transmission power in a feeble attempt to yell/take over the frequency for themselves.
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If you have 8x 100Mbit wires in your house, that's closer to 1600Mbit true bandwidth (100Mbit per direction across 8 devices).
I have the same issue, but lower speeds. I have one cable that will negotiate 100Mbit rather than the 1Gbps that I expect. For a week it has been 100Mbit only (which is technically fine for the purpose), then two days around the router fell down and now I get 1Gbps.
I suspect a badly installed or wrong choice of keystone.
A lot of equipment you can buy today still only goes up to 100Mb/s, and a lot of houses still don't get even that from their ISPs.
Even if you have a gigabit connection, most of the time the computer at the other end isn't going to be sending you data at gigabit speed.
You might want gigabit speed to support multiple devices. But most houses don't have that many devices consuming high bandwidth at once, and when they do, you can feed them with multiple wires and/or access points.
All of this is to say, for almost every house, the standard cable from 1995 is still perfectly adequate. Cat5e will probably still be fine, by the time you sell your house.