While Atlassian is free to remove a feature or to deprecate a feature, tt seams that there was no 'deprecation period or it is a lot to short'. (packagist.com was launched in Dec. 2016 and this feature disappeared before end of Feb. 2017). This deprecation seams to not effect older accounts, as a packagist co-founder confirmed.

Please enable this menu point for new accounts, too (and place a deprecation warning),
to give all users and integration partners enough time to miragte to app passwords.