But as it is across Europe, then by your own admission, we're going to continue to see variants and the passport system won't be temporary.
Citation needed for "as it is across Europe" - don't be misled by some of the more hysterical reporting about Europe in the media. Because eg
the YouGov tracker has much of Europe at around 70% being likely to get jabbed, which is where the UK was at Christmas. Yes, France is an exception at around 50%, but in general I think you'll see a general growth in confidence as people see their neighbours getting jabbed, and the message gets through that yes the jabs are pretty safe. So I'm fairly relaxed about that.
I'm not clear what you think the "desired effects and goals" of vaccine passports are
To keep vaccinated and unvaccinated people from mixing.
Well obviously that's not going to happen, as most mixing of vax/non-vax will happen in the home and in non-passported places like supermarkets. You have to look at this in the context of tension between keeping things closed down to purge the virus, and opening up the economy again.
The purpose of vaccine passports is to save the Treasury furlough/subsidy cash, by allowing economic activity to happen that would otherwise be closed on medical grounds. The thinking is that opening up to 60% of the population is better than being open to 0% of the population - and although few will spell it out loud, the opposition among publicans is mainly on economic grounds, they suffer more being half-open than being completely closed.
Now obviously events have overtaken this thread, yesterday Johnson said that they wouldn't be passporting pubs at least for now, but it's almost certain for international travel and highly likely for "mass gatherings and indoor events" such as sports matches and nightclubs. Personally it feels like we're on enough of a knifeedge at the moment that as at Christmas, large numbers of deaths will turn on apparently small decisions where Johnson's need to people-please overrides the need for unpopular decisions, but we'll see. So much depends on what variants we have in the UK in the summer.
A secondary goal of passports is to help employers observe their obligations to provide employees with a safe work environment - since most barstaff are too young to have been jabbed yet, they are at risk from any infected customers that come in a pub. If all customers are vaccinated, then customers are far less likely to be infected (but not guaranteed to be so) and are far less likely to transmit to barstaff if they are infected. That makes the barstaff much safer - without reducing their risk of infection to zero. It's a bit like requiring everyone who drives a car to have passed a test as certified by the possession of a driving licence - it doesn't guarantee that they will always drive safely,but hopefully it will reduce the risk to other road users.
Vaccine acceptance may have increased, but it remains to be seen whether the young will be vaccinated in the numbers that the older people have. Again, by your own argument, we're not safe until we're all safe. How do you square that circle?
I think the onus is on the pessimists on that one. If we're seeing ~95% vaccination among the over-50s and 85% among the 18-49's (and hopefully the trials on teenagers will be complete so we can start on them too), then that is getting to the kind of levels where "classic" Covid is under control. So vaccine reluctance is fairly low on my list of things to worry about, apart from a handful of countries like France and Hong Kong where more work needs to be done.
From a UK perspective, we've got enough people willing to be jabbed to keep the pipeline going for a good 3+ months, and then we see where we are.
I'm more worried about things on a global scale, all this stupid squabbling with the EU has distracted from the need to get vaccine to the countries which really need it like Brazil, which seem to have a healthcare system on the verge of collapse - they've had
22-year-olds dying whilst waiting for an intensive care bed.
I'm certainly not averse to restrictions being in place to protect lives and keep our health service functioning, but there comes a time where the level of risk is deemed acceptable.
The trouble is, people are pretty lousy at assessing risk, particularly in the early stages of an exponential curve. Remember the thing about one grain of rice on a chessboard and then doubling it every square until you end up with over a trillion tons of rice on the board? This is one of those kinds of situations.
And we now have the proof that the way to get out of this is hitting the virus hard and early, harder than people "think" is needed "given the risk". The countries that went hard from the start, like Taiwan and NZ, are now pretty much back to normal, whereas countries like US/UK that had politicians that were consistently behind the curve and reacting to events, are still struggling with economic restrictions.
I completely understand the instinct to only respond when it feels like a "risk" is present - but that's almost always too late. Conversely when relaxing restrictions, slow and steady is the way to win the race.