Because someone who needs ICU intervention even if they are young is unlikely to come out alive anyway without that ICU intervention.
You are comparing apples and oranges.
Its true a young healthy person who gets covid, will almost always come through unscathed without need for hospitalisation or any medical treatment at all. But those individuals aren't preventing an older person who is seriously ill from accessing an ICU bed or other treatment.
Very different from the rare case where a younger person gets seriously ill with covid and actually needs medical intervention in ICU (due to their other underlying conditions). In that case, if there are ICU bed shortages and a doctor is choosing who gets the ICU bed the seriously ill younger person or the seriously ill geriatric person, all other things being equal it would generally be prudent to prioritise the younger. Tough choices get made all the time.
Was the issue (ethical) that of an eldely person with Covid-19 vs a young person needing ICU,
not a young person with Covid-19 needing ICU? That makes a massive difference in the number of 'young' person ICU admissions.
Having had three close relatives who all sailed through their 90s - two of whom were active (walking briskly, gardening, shopping) until literally the last minute (one had ordered her breakfast in bed, unusually, and when it arrived she had died) through to 98, 99 11m 20 days (missed out from her much desired card) and 101 (proud possessor of the card, and said 'You'd thought she could have given me a better smile') - I was very thankful that they were not around when Covid-19 struck with all its issues for isolation.
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Back to elderly covid-19 patient vs young (does that mean under 65? Under 50? Under 40? Under 30?) patient getting priority for an ICU bed.
Given the life expectancy for someone who is 70 years old is to live to a greater age than someone who has reached 50, which is greater than for someone who has reached 40 etc etc. The actuarial tables are there for all to see.
What if this 'young' person has some issue that is 'socially' frowned upon - such as long term illegal drug use (that has severely damaged multiple organs hence need for ICU ), drunk driver who has just wiped out three children walking on the footpath, or some societal 'worst' habit with criminal convictions (murderer, rapist, paedophile etc)?
There are restrictions on who is eligible for organ transplants (which are somewhat public), so is it that much of a stretch for the community to ask for similar transparency about ICU admission?
Anything otherwise seems to be just socializing 'Russian Roulette'.
Attempts to deflect this question by saying there are few 'young' Covid-19 patients put into ICU, to me, is irrelevant. The issue seemingly is ageist, not Covid, related.
. Agree. How did this thread get here! 
