All the reports I've seen so far recommend caution, typically saying that Omicron is highly contagious, possibly more so than the delta variant, but it is not yet clear whether Omicron will be able to displace Delta. Where did you see the definitive 5x figure?

The South African doctor who first identified the Omicron variant says in this Telegraph article the symptoms are unusual but mild, however the age demographics in South Africa are that older people only form about 5% of the population, so the effect on older people isn't so clear.

What the epidemiologists are praying for is a super contagious variant with mild symptoms. If this took over completely and spread across the world the dangerous part of the pandemic would be at an end.

As soon as the virus enters the human host it rapidly replicates itself and sometimes errors are introduced into the copying of the RNA, creating a variant (thousands to date). What seems to happen in a few very rare cases, rather than the patient fully recovering, the virus remains active, potentially mutating over and over again as time passes. Some of these mutations are 'drifts' in which a single change occurs, the worrying ones are 'shifts' with many changes and it's thought the 30+ changes to the protein spikes with Omicron variant happened in a single patient. That mutation probably happened somewhere in Africa which is why Morocco suspended flights from six southern countries, but it was South Africa that identified cases in its country through genome sequencing, and gets the blame, just as the UK got the flak over the Kent variant.

EDIT: Jay's post must have come in after I started to type, but our thoughts are the same.

__________________
"For sheer delight there is nothing like altitude; it gives one the thrill of adventure
and enlarges the world in which you live," Irving Mather (1892-1966)