Sure, we'll get there, and the basic argument (maximise herd immunity amongst those to whom it's no threat) makes sense twice over: it reduces the risk to the vulnerable, and it lets the non-vulnerable get on with life.
It would be difficult to argue with that if it were not for three important points -
1. Given the long-COVID issues, where many younger people who have had the virus seem to have lingering long-term health issues that we simply don't know enough about at this stage, it's clear that we're not really in a position to say 'non-vulnerable' other that for it to perhaps mean 'you're unlikely to die from it' for large sections of younger society..
2. Herd-immunity might well turn out
to be the only tool in the box, but given the number of global vaccines currently undergoing Phase 3 trials, with many more in Phase 2 trials as well, and given Point 1 means that a rush to herd-immunity using the young as guinea pigs might well mean leaving a generation with long-term health issues, I think it's right at this point in time
to resist having to rely on herd-immunity to to get us through this. I note that the Phase 3 Oxford vaccine trials, which is one of the most advanced in the western world, has now been given permission to resume, following a brief pause last week...
3. Whilst the rising number of UK cases don't seem to be feeding through to hospital-admissions right now, it's too early to say if that situation is going to be maintained, and especially given the coming colder weeks and months of a UK winter. We don't know at this stage where the peak of the current UK wave of cases is...
Like most things, it's a balancing act based on known data at the time, and I think those calling for encouraging large-scale herd-immunity in younger age-groups, with a view that a widespread immunity level in those age-groups would then automatically protect older, more susceptible age-groups, is perhaps risking the long-term health prospects of many within that younger section of society, given the lack of current knowledge around these 'long-COVID' issues..
I personally think a more cautious approach whilst we wait for some of the Phase 3 trial results is the right way to go at this stage. Whilst it's clear that many in the younger population are making their own minds up by perhaps going against the current guidance in many cases, I think that's a completely different situation to one where we'd be seen to be actually encouraging
them to be our 'herd-immunity' guinea pigs...