SCOTUS will pick off every place where there are gun constraints. DC will be next -- so TFG's

Per University of Texas law Professor Steve Vladeck, the decision isn't quite the apocalyptic live-fire zone ruling some may have anticipated, explaining "Kavanaugh and the Chief make clear in their concurrence that the Court is only striking down six states' 'may-issue' laws. The 43 states with 'shall-issue' licensing regimes 'may,' in their words, 'continue to [have them],'" making it sound as if a simple legislative patch would restore the permitting systems but require applicants to demonstrate a clean record rather than an affirmative need to carry a weapon.

They ruled that states are free to condition licenses based on objective requirements, whereas some states were previously using subjective requirements. They’re simply stating that if an applicant meets all the objective requirements that have been set by the state, the state cannot deny them their license.

You have to take the training, register the gun in DC etc etc. If you follow what they have written for the requirements they have to give you the license. They cant not just say no because they want to in DC.

From what I have read the biggest hurdle for people who do not live in DC is registering the gun with DC. And thats just paperwork, people who live there have to register it anyway so its a step they dont have to do to get the license.