The elephant in the room of course is the fact that at every ground there is probably somewhere around 15%-20% of the ground that stands anyway. It’s clear for everyone to see on tv even if you’ve never been to a game, yet officially it doesn’t happen. And it’s not - technically - ‘safe’ when a goal is scored, although it’s usually a few bumps and bruises that might be sufferered rather than anything too serious. Yet for many it’s fundamental to their enjoyment of attending football. (Personally I much prefer standing).
However, no club can officially say “well,we have standing anyway in an uncontrolled environment, so safe standing rail seating would actually be an improvement on the current situation,” because they would be in breach of their safety licence and would be breaking the law by not enforcing sitting down.
Therefore it’s easy for politicians to brush the subject aside - why change an all-seater rule that appears to be working fine? It will take something major to happen (eg a crush, someone toppling from an upper tier) for it to be looked at seriously - and even when that ‘something’ happens, it will be the fault of the fans and the club in question - and it will be said that football fans can’t be trusted to stand. Vicious circle.