Smart people often make the mistake of assuming that other people are smart too, and to be fair to the RHA and anyone else who had to rely on the current UK Government, self-destructive insanity can look exactly like steely brinkmanship right up to the very end. I think the RHA were expecting cabotage to be retained as a bare minimum as part of any deal, because it was essential to the running of the UK economy.
Cabotage is the right of a driver from one country to make deliveries between two points within a second country, and it’s an essential part of keeping up the efficiency of international road transport. For example, it allows a driver who came from Italy to drop off in Sunderland, collect there, drop in Birmingham, collect in Coventry, drop in Swindon, and then pick up there for their trip out of the UK. The two trips within the UK require cabotage rights, which EU drivers no longer have after Brexit. (The same applies to British drivers in the EU, and while this made news earlier in the year when various British rock-bands complained that it would be impossible to tour without it, although none of the news reports I read followed the logic through and considered the implications for freight within the UK.. )
Basically, the UK has a large internal market with lots of goods moving within it, but the country exports far less physical goods than it imports. Without cabotage, you need extra drivers within the UK to do internal deliveries, while also sending empty trucks back over the Channel.
