> many large TXT records can be abused for DDoS purposes. dig -t txt ebay.com for a DDoS Example used today

What does this mean, I see a bunch in the lookup but I don't understand the ddos part

If a site has a large set of TXT records, they can be used by clients that spoof packets to request large volumes of answers by DNS servers. This is called an amplification attack. Many tiny spoofed requests in, many large answers out.