The key part of your question is that "2000 hand reg" domains. If that portfolio was built up over say the last 20 to 25 years, then yes. With careful investing, avoiding just about all the trashy extensions. Then probably with due diligence including watching the Drops + studying future developments in technology, having an investors mindset you'll probably end up with a good second income (not so sure about a Primary income).
The bottom line is -Your own intelligence level comes into play. Don't forget you need at least $20,000 a year just to earn a big fat Zero. Plus if your that good at domains over the last 20 years plus you would have probably moved onto the drop/auction/buyer market by now So now your either totally broke or living nicely off you wits.
Is it a good investment plan to start today. Absolutely Not with hand-registrations