Have you looked at whose on this Committee? An Earl who rules us by virtue of medieval hierarchy, a couple of New Labour old hands who told us for years that the countries banking model was sound, a Tory of 30 odd years time as an MEP, who led the successful fight to defeat an attempt to make their entirely tax payer funded pensions partly contributory, and then was one of the architects of the Coalition reduction of public sector staff in the UK, (hypocrisy on steroids!) and so on. No doubt they cost us a fortune in expenses claims as they prepared this meaningless report.

The EU will refuse to export anything to us, even if it affects their own economies

Not at all, that would be an outright trade war or even some form of trade blockade.

A disadvantaged trade deal for the UK would simply mean it having to pay tariffs (taxes) on good it exports and imports to the EU.

Why wasn't this in-depth investigation and modelling done prior to the Referendum?
Total incompetence and arrogance on behalf of Parliament!