I agree with you on Brexit, austerity. But you can always find an expert briefing in yr direction cf Walters, Lawsom, Thatcher

The politicians did defer to expert and business opinion over Brexit. The referendum was only called because they thought they would win it. I personally think it was a good thing, but the politicians definitely did not - the point was a referendum win would fatally weaken the leave movement. An interesting irony is that polls before the referendum in the 70s suggested people did not want to remain, the ones before 2016 suggested they did.

Lots of experts favour austerity. The trick with economics (and many other things) is to find the experts who agree with out.

The government did listen to experts over covid. Whose idea was lockdown? Who advised them that a rapid vaccine rollout was required. The government did get confused by experts having different opinions (as one would expect with a novel disease) but once convinced which experts they listened to they did follow them. The main fault was not balancing advice from experts in different areas (e.g. balancing physical health, mental health and economic impacts of lockdown correctly) which is exactly what I was complaining politicians fail to do