fool and his money
while being throttled there's more than enough bandwidth for gaming. what's far more likely is that there was some sort of issue with your connection; going to 50 meg involves changing from DOCSIS 2 to DOCSIS 3, and an engineer visit. Chances are whatever they did resolved your issue.
and let's not have any crap about "using what you're paying for"... you're on a consumer broadband connection. You're paying for a contended service -> you are getting what you paid for, unless you're paying at least 3 figures a month