I switched jobs earlier this year for a 47℅ 'raise' - I'm absolutely loving my new role.
My understanding is that a potential sale of my previous employer fell through because I was basically the brains that developed / maintained the only innovative thing they had done in the past 15 years, and given their lack of investment in anything else there was nothing else of value for the buyer.
Because they aren't overriding it - the legislation allows for these rent increases in certain circumstances. Not agreeing with the law or the decision, but the arbitrator isn't making up some new power.