I don't consider 100% the goal since I'm happy if the average squatter/spammer/landing-page maker finds no value in steps to reaching more discerning clients given correlating filters. It seems likely to me that the percentage is near the tipping point where any serious organization is probably doing DNSSEC or having discussions about why they have IT problems and should be as serious now as they are for the email standards. For example, the validating DNSSEC looks higher than domains with functioning DKIM usage:
https://stats.labs.apnic.net/dnssec?s=Validating&d=01%2F06%2... https://stats.labs.apnic.net/dnssec?s=Validating&d=01%2F06%2... https://stats.labs.apnic.net/dnssec?s=Validating&d=01%2F06%2... https://stats.labs.apnic.net/dnssec?s=Validating&d=01%2F06%2...