I graduated in 1998 and got a retail job in the Trafford Centre when it opened in September that year - £4.12 per hour. Under 18's were paid £2.12ph for the same job, and 18-21 year olds £3.12ph. My food shop was something like £30 a week, and diesel was 60-something pence per litre.
I went back to my home country for the first six months of 1999 and remember being shocked at how much food prices had jumped in that time when I returned. A single green pepper was 73p, and a pineapple was £4. Household goods and clothing was expensive too. A fairly basic desktop computer was around £1,000. The idea of disposable fashion would be laughed at. Interest rates had also risen quite rapidly since the 1997 general election when Gordon Brown gave interest rate-setting independence to the Bank of England. Inflation had been high and was just coming under control. Then came the dot.com crash, which was deflationary.
What has happened since then is interesting, because the turn of the century was when international trade really took off and we were able to 'export' much of the UK's inflation. The cost of almost anything that is now manufactured in the Far East - clothing, electronics, furniture - began to fall quite rapidly both in absolute terms and relative to incomes. Same for things like pineapples, which are now 98p, although a single pepper is still around the same price as it was in 1999. It helped that the Asian financial crash and currency crisis was extremely deflationary in many emerging markets there too.
At the same time, Gordon Brown flogged off all the gold and borrowed like there was no tomorrow, and he redistributed all that money to people through tax credits. Freedom of movement and the EU enlargement helped keep a lid on labour costs to businesses, but incomes were then topped up by government. So, although the average Brit's productivity started to decline in the early Noughties their incomes actually went up, as prices were coming down.
The years 2000 to 2007, when everyone in the UK got better off in aggregate, turned out to be entirely illusory. What's happened since then has mostly been an unwinding of those fateful Gordon Brown years, augmented by huge policy car crashes associated with the Great Financial Crash and covid, and crowned by Brexit.