Having used Victoria for 30 years on and off, but many times a week over the last few years, it seems to me that the influx of TPE services have changed the role of the station somewhat - it was previously mainly a start or end point of a journey, now there are far more passengers changing there.
As such, the lack of facilities on the platform side of the gateline is pitiful. No toilets, no catering, few seats, even no proper information provision as the only screens showing full details of all services are on the other side of the gateline and angled so that seeing them from the platform side is nigh on impossible (there are screens showing summary level departures but these can’t be used to clarify intermediate stops)
There are also reports elsewhere of gateline staff refusing to allow passengers to exit in order to go to the toilet and re-enter.
As long as Northern are responsible for the station, I can’t see anything being done about it.