Meanwhile on the Roads...

Pretty much every adult in the country either drives every day or has a driving licence but for various reasons doesn't drive regularly.

Pretty much everyone in the country now sees car ownership as a basic right and minimum indicator of being a successful/ functioning adult.

We each see the world through a different lens. By your definitions, I'm clearly not a succesful functioning adult, having no cars, no driving license, though do own and run a business, have been an employer for three decades, own a couple of properties that are fully paid for, and of course own two bikes :) Also anecdotal, but I know very many households with two or more adults (grown up kids) which would have a single car, not one per adult. I know numerous younger adults of my daughters' generation (mid 20s) that are more interested in getting their own place and see car ownership as a blocker to this. e.g. neither of my daughters (22 and 25) has a driving license, both are moved out (one now in London to be fair).

Less anecdotal, as of 2025 Ireland has 466 passenger cars per 1000 people. Given the demographics of the country, that is a lot less than one vehicle per person without looking at the number of commercially owned vehicles and individuals owning multiple cars. As for driving licenses, if every adult had one, why the backlog for driving test applications given you need to be an adult to apply?

That's why I also looked at population demographics in Wikipedia, see below

If we allow an even distribution in the groups, we'd allow 70% of the 15-24 being adult (8.43% of population) and say 50% of the over 65s being less than 75 (6.6% of the population). This leaves us with 68.5% of the population being adult between 17 and 75, as opposed to 466 passenger cars per thousand or 46% of the population before looking at individuals owning multiple cars. Given a population of 5.38 million and a difference of 21.5%, that's 1.15 million adults in this country who are apparently non-functional or unsuccessful by @Paddigol's criteria. You can imagine how those of us that neither drive nor have any interest in cars might take the hump reading such an aassertion.

Edit: FWIW, last CSO poll shows 81.6% of adults over 18 with driving licenses which tally's with the above, which is a far cry from 'Pretty much every adult'.