After a certain amount of fingerprinting, absolutely. It's not as if they are solely relying on user-submitted information such as a handle to make that link. And if no link can be made right this second, they can just continue to collect data under "InteretDude420" until they reach a certain amount of confidence to link it to a real identity.

And, even if they get it wrong some % of the time, who would ever notice or find out? Eventually they just get more data and increase the confidence rating for the correlation.

It is surprising how little information (even "anonymized information") is needed to de-anonymize someone. Plenty of papers on the subject if you are curious.