The list of reasons really is too long to include. From the continued worsening of individual bits of tax legislation such as IR35, dividend allowances, employers NI, corporation tax, etc. to the stalling of real GDP per capita combined with an increased population and the consequentially stretched hospitals, transport, etc, the draconian policing of social media... it's pointless me trying to list it all really.

Dubai is a bit of a trigger for some people. Others I know are going/gone to Portugal, Malta, Cyprus, the US, Aus, Can, NZ, Singapore, France. Your mileage may vary - people leaving can generally give you similar lists of why, but where they go seems varied.

I used to live in Saudi for a time (25+ years ago), and actually really liked much about it then and it had changed markedly when I've been back more recently. I've visited Iraq, I've been detained in Oman under suspicion of espionage and still see virtues in the place. Dubai is positively liberal by comparison and becoming more liberal, while the UK is becoming more authoritarian and despite the official crime statistics, I'm not sure it's as safe as it once was.