Yes, as
@Snow1964 said, the TFL contracted operation of 'heritage' route 15 was suspended during Covid and never re-appeared.
Londoner Buses started route 'T15' (Tower Hill - Charing Cross, journeys to / from Waterloo) as a commercial venture outside the TFL network (so premium fares charged, travelcards / oyster not accepted) in 2023.
(although any non TFL service operating in London still needs a 'London Service Permit' from TFL)
I have not heard / seen anything to say it has been withdrawn, but the question came up on another forum a few weeks ago from someone who had tried to travel on it and it hadn't shown up on the day they tried.
Web searches bring up a few PDF timetables, but there's no obvious mention of it on
Londoner's website, and
their Facebook page hasn't been updated since June.
At one time, you could download a list of current London Service Permit routes from TFL's website, but this doesn't seem to be possible now.