Not true. The theoretical maximum a few years back for Ethernet was 10Mb, but commonly today's standard is 100Mb.
Wireless connections are more like 11Mb. If I want better connection to game servers, then I connect my laptop to the wireless connection to remove latency. So... Wired is usually better performance.
Really, though, if you're in a FTTH (fiber to the home location), then most likely your ISP (internet service provider) is really what is slowing you down. I mean... I have a 7.0Mb connection, and that's a fatty connection for where I am. FTTH can do "anything." They sell it in 15Mb packages in some places:
This site even gives Fiber less than their normal 'premium' broadband. I think you know what the future will be.
Anyway... I ramble. Good Luck!