It should but that is assuming the problem is the wifi.
If you ping the IP address of the router and you see these large ping spikes then a ethernet cable should help.
This unfortunately is one of those things you need to actually test. It is extremely common for wifi to cause this but it can also be caused by over use of your internet connection. If some other devices in your house are using all the download or upload speeds you pay your ISP for you can get large delays also. That at least you can do something about by getting some agreement on usage or maybe buying a larger connection.
In general when things are working properly the ping is a measure of distance. The path though is not always direct so sometime the...