Ofcom guidelines;
8.1 Any infringement of privacy in programmes, or in connection with obtaining material included in programmes, must be warranted.
8.11 Doorstepping for factual programmes should not take place unless a request for an interview has been refused or it has not been possible to request an interview, or there is good reason to believe that an investigation will be frustrated if the subject is approached openly, and it is warranted to doorstep. However, normally broadcasters may, without prior warning interview, film or record people in the news when in public places.
In this section “warranted” has a particular meaning. It means that where broadcasters wish to justify an infringement of privacy as warranted, they should be able to demonstrate why in the particular circumstances of the case, it is warranted. If the reason is that it is in the public interest, then the broadcaster should be able to demonstrate that the public interest outweighs the right to privacy.
https://www.ofcom.org.uk/tv-radio-and-on-demand/broadcast-codes/broadcast-code/section-eight-privacyIn my opinion the 'public interest' was not a reason for doorstepping in this instance, and could not have been demonstrated to outweigh the right to privacy. That's because 'public interest' can't be defined by ten 'outraged' people and one news organisation.