My view is that the 3 weeks review will take us to the end of June when it will be relaxed. Ryanair and others have decided they want to restart in July and that's what'll happen.
How much would you bet on that? Would you book a holiday for July with the possibility of having to self isolate for 14 days on return?
The arguement for not having quarantine earlier is that the level of infection in the population was so high that the amount imported made little difference and the greater good was allowing people to repatriate. Once the general level of infection becomes low enough, the possibility of a 'second wave' due to imported infection becomes significant and so needs to be controlled.