The UK still have plenty of qualified drivers. Short-haul drivers have to be paid either the minimal wage of a country of the negociated sector wages if the sector Union is good. The Unions in the UK are worse than French unions (i wonder how it is possible) and did not secure any minimal guaranties, the drivers takes those minimals from EU + national laws. And while the pay is not that poor compared to other EU countries, HGV drivers also used to have a tax break and bonuses for crossing the channel. Now i think they lost this advantage (from what i understood). Also long haul UK -> portugal, UK-> Italy were probably the best paid trips, and are now filled by French drivers (probably other EU drivers too).
From what i understood, short-haul are the worst: worst pay, you have to get off your truck and help the stock or factory workers fill your truck if you don't want unbalanced cargo or worse, the hour are not much better than long haul except you don't have bonus day off.
> The whole thing was an artefact of EU rules specific to lorry drivers that allowed them to work here using cheaper (and I think less stringent) qualifications from elsewhere whilst also living elsewhere
No true for local haulage. For long haul, you do have companies who plot the trips to go through let's say Poland so they can take Poland's minimums on pays and qualifications. Not true for all EU long haul though (Uk-France it is quite expensive to cheat)
[They work(ed) in the motor and film industries, the benefits and pay being in a completely different ballpark to haulage, even though driving large vehicles was a small part of the job]
Anyway, the whole point is that those drivers who've left don't actually have the licenses and training to drive in the UK and couldn't afford to live here. The whole thing was an artefact of EU rules specific to lorry drivers that allowed them to work here using cheaper (and I think less stringent) qualifications from elsewhere whilst also living elsewhere, and of even the minimal restrictions there were on things like rest time outside of their cabs being effectively unenforceable. Without the weird distortions caused by those EU rules there's no way to get back to where we were, and opening up immigration wouldn't do it. Also, those rules were causing problems here and elsewhere in western Europe before Brexit, and there was already a substantial shortfall in drivers back then too, so it wasn't a sustainable situation.