Not everyone chooses public transport because they have no choice.
I could finish learning to drive and own a car but my public transport costs are less than the car ownership costs so the incentive isn't there.
It costs me £4 to get to and from Guildford to Kingston upon Thames by bus, when I need to go to an office. Bargain. No car could match that.
The situation at Brighton is an annoying one, though, if you are a regular commuter. I don't know why they don't just leave the barriers up all the time to stop people switching platforms more easily. Make them always enter and leave the gateline, if it's so important to them.
I do suspect there might be lunch breaks and tea breaks. May be there are regular times every day and if you travel through Brighton often enough, you will get to know them.
I've certainly come across this elsewhere. One usually only notices such patterns when they travel regularly, and to travel regularly, where ticket barriers exist, one needs to have a ticket or they will get caught without one.
To be honest, if they really want you going through the gateline forever, its inevitable theyll get a proper permanent barrier at some point so the platforms are completely separated from each other, unless people absolutely have to rapidly change platforms in the case of disruption leading to a platform switchover.
To be fair with public transport, usually although there are always alternatives, including alternative modes, most of the time the choice is pretty obvious. While there are plenty of buses into Brighton, buses get a bad reputation for being slow, and before the fare cao, ludicrously overpriced. For many journeys, that leaves the train as by far the best choice for many into Brighton, considering parking is a nightmare in Brighton, leading to park and ride locations.
For example, one of my most frequent journeys recently is Bognor Regis to Lancing, and while the bus is substantially cheaper, it would take twice as long, and plenty could go wrong, such as traffic jams. Therefore the choice to use the train is pretty clear, as i dont drive. However, given how flexible the car is for many journeys, the choice to use that is so clear.
Although many people have the choice at using Brighton station, ultimately if poor customer service goes too far to the point that they could end up with crushes like the ones at Euston if they continue to insist on dozens of officers and limiting ticket barriers you can use for each line (particularly given East and West Coastway are now separate barriers), this could motivate people to use the alternatives if they can improve in response to terrible stories about Brighton station (E.G. more express buses to places like Haywards Heath and other intermediate stations to take in people making local journeys into Brighton stations).
Also, excuses like 'allow more time' i absolutely agree is a load of rubbish, given they basically gave it no thought as to how they could have allowed that, which would have been by placing some officers at the point where you currently cant cross directly to check to ensure the ticket you have is valid, rather than leading people into a gateline based on outdated 1980s technology leading their ticket to be wrongfully rejected, and miss a tight connection as a result.
By the way, with all these officers around on railway, it by no means is a GTR only thing. I had a ticket rejected by a barrier at Vauxhall changing from SWR to Victoria line, and I was asked to show my railcard to the barrier operator at the height of evening peak time. That is easily annoying, because doing that just leads to miss connections, particularly had i been changing from Victoria line to SWR and getting a line with just an hourly service, where a single check can lead to missed connections and lengthy delays that staff actions were responsible for.