That's incorrect. England and Wales have 8, Scotland 9 and Northern Ireland 10 - see here:
https://www.gov.uk/bank-holidays
Although the extra "bank holiday" in Scotland is St Andrews day, which was introduced in 2006. In my experience virtually no-one seems to observe it, no doubt in part because banks aren't actually obliged to close on St Andrews day, and employers aren't obliged to give staff the day off:
https://www.gov.scot/publications/bank-holidays/. So it's not really much of a bank holiday, more just a bit of ScoGov flag-waving.
Although 2nd January is a bank holiday in Scotland, Easter Monday isn't. So if you ignore the St Andrews day holiday - which seems to be generally the case - then Scotland has the same number of bank holidays as England does. Personally I'd rather have had the extra day off in the spring rather than in the middle of winter, in Scotland. But I'm retired now so every day is a holiday for me anyway
The local or public holidays in Scotland are another matter. They seem to be observed in a rather haphazard fashion; for example in Edinburgh the council offices are closed on a local public holiday, bin collections don't happen, and Lothian Buses run a reduced service. Some shops - mainly locally owned and run ones - stay closed, others don't. None of my employers ever gave me the day off, though ☹️ They also don't seem to be particularly widely publicised: the first inkling I usually get is when Lothian buses announces that they will be running a reduced service, about a week beforehand.