I asked Google and it told me I was absolutely correct. So… ;-)

Loneliness rates vary by country, age, socio-economic status, health, etc. The UN has some reasonable statistics.

https://www.who.int/teams/social-determinants-of-health/demo...

There's also some detailed stats for the UK.

https://www.gov.uk/government/statistics/community-life-surv...

Was my use of "most" careless? Probably. Let's natter about it over a pint.