As I understand it, basic PHRF ratings are adusted by each local racing authority to fit the local conditions and characteristics of the fleet. PHRF includes to some extent crew capabilities as observed over time. For instance, the boat I sail on came in 3rd overall in its division of 12 or so boats in the SF bay OYRA racing last year. As a result, our PHRF was increased slightly, while the PHRF of the boat that finished first was decreased slightly. Boats that consistently out-perform other boats for no apparent reason other than crew skill pick up more PHRF points to balance things out.
Also, bear in mind that PHRF ratings are arbitrary measurements that can''t come close to predicting the performance of all boats. What seems to work in windward-leeward races doesn''t work in olympic or random-course races.
The person you were talking to might also be referring to other issues, like the state of your sails, rigging, balance and weight distribution, etc, which can certainly cause performance problems that would make your boat slower than its nominal PHRF rating.
That being said, if you want to race, race. Don''t worry about the competitiveness of your boat. Get it in the best condition you can afford and get out there. It takes a couple of racing seasons for you to establish your true position in the fleet.