That proposed 14-day mandatory quarantine period will kill virtually all passenger air travel stone dead. What business executive can travel on those terms? What employee can return home from their annual holiday only to phone into work to say they're in great health but they're entering two weeks of quarantine? This proposal would be quite catastrophic for economic recovery, let alone for the commercial aviation industry.
Practical measures with quantifiable payback make sense. Blunt instrument proposals do not. Arriving passengers should be administered a quick C-19 test, should install an NHS 'track and trace' app on their phone, and should wear a face mask in public spaces. Most passengers would accept these measures as enduring the inconvenience makes sense for the greater good. Compulsory quarantine for all will simply destroy the airline industry and hugely damage the wider economy. And I'm very sceptical whether it would prevent any significant C-19 risk over and above the sensible measures just outlined.
The airline industry must lobby with urgency for common sense solutions only.