If following that guide you used this line in your nginx configuration:
You should replace that line with
then restart nginx and try the Qualys test again (click on clear cache on the Qualys test page if necessary). You can compare the results for the simulated connections by different browsers and search engines to see that nothing changed except you lost the ability of Internet Explorer on Windows XP to connect. That is not a loss, it's completely insecure.
In the future, when you upgrade from Ubuntu 14.04 to a server OS that ships with a version of openssl that supports ChaCha20Poly1305, you'll wany to adjust the ssl_ciphers. This can be as soon as when Ubuntu 18.04 is released a year from now. You'll definitely need to adjust when you switch to Ed25519 certificates, which will take a few years (RSA 2048 certificates will probably be supported for a very long time, and Ed25519 will not become available for at least a year, but eventually everyone will upgrade).