The great eye-opener of Brexit is that it's shown us how unfit many of our politicians are for the job.
This is mainly due to the UK electoral system. The FPTP system means that the only real "talent" every MP needs is the ability to win an election in his/her constituency.
But the problem is, that produces a monotone breed of MP who can do very little else. You don't have to be intelligent or informed to win an election. You just need to be good at public relations. And in safe seats, it's often enough justto toe the party line.
All of this is a major handicap when it comes to deciding big issues. Having no experise themselves, ministers are reliant upon the opinions of civil servants, while MPs are reliant upon the official party line or political think tanks. Most have no grasp of the issues itself
In Germany, for example, the electoral system is different. Parliament is made up of both constituency MPs and MPs who are elected via PR on a party list. This extra party list means they can have MPs in parliament who have areas of experise other than just winning elections
Of course, nothing's perfect. In all countries there's an increasingly low variety of backgrounds amongst MPs. Most are lawyers or union reps, very few are scientists, philosophers, artists, engineers, etc. But the UK system in particular seems intent on producing "thick" MPs