Administrative law is inherently less democratic.

Than what? You can argue with the article:

The claim that administrative agencies lack democratic accountability is one of the frailest arguments from conservative activists. Congress has established a plethora of checks to ensure constant and persistent accountability—something that unelected and nearly unremovable federal judges fundamentally lack. Consider that agencies do not just exist; rather, Congress must create them. Congress sets agencies’ budgets, which determine their operations. The laws agencies enforce are enacted by democratically elected members of Congress. Agency leaders must not only get nominated by the President but then be approved by the Senate. Most agencies require their leaders to meet frequently with lawmakers and submit reports to Congress explaining their recent enforcement actions.

Agencies also cannot just enact new regulations at will; they must justify them with substantial evidence. The published regulations are often hundreds of pages long, with many of those pages devoted to discussing the evidence and clearly explaining the rule and its effects.

There’s also accountability measures built into the day-to-day running of these agencies. Enforcement actions and other activities must be published in a government-wide daily publication known as the Federal Register. Agency rule-makings that enact new legal obligations require extensive public comment (in some cases extending for more than 60 days), and in limited cases, even multiple rounds of public comment. Moreover, those rule-makings and enforcement actions are eventually subject to judicial review by a circuit court of appeals. All of these processes ensure that an agency’s actions reflect the will of the people.

Congress can also negate specific agency enforcement actions with a simple majority by invoking the Congressional Review Act. And, of course, agency officials are always subject to ad hoc meeting requests from Congress, which usually occur in response to a national news event. In summary, democratic checks on agency actions are abundant.

What exactly makes all of that inherently less democratic?

More importantly, though, to the extent that it is less democratic (if it is...), is it as undemocratic as judicial power?