1. An txt record adds more time to the request, since you can't start the request before opening an tls connection. 2. The browser has to go through all the TXT

1. An txt record adds more time to the request, since you can't start the request before opening an tls connection. 2. The browser has to go through all the TXT records. My domains already have 4-5 TXT records. 3. The dns is still pretty much insecure. Dnssec is still not always available