Joppa

Home Office until late 70s/early 80s used to issue visas free of charge, as well as registering as British citizen. The only thing they charged was naturalisation, at £180 for someone married to British citizen and £240 for anyone else. They they started charging just to cover the cost of the service provided, which was around £200 for long-stay, family reunion visa. Then they began to charge an amount which will offset the cost of delivering the immigration and nationality service as a whole (so that British taxpayers don't have to subsidise), hence thousands you now pay for registration, naturalisation etc if you add all the visa and other fees you pay up to citizenship. The only other country to my knowledge to do something similar is Australia, but they charge something like £4,000 up front, which covers all the fees up to permanent residence.

DavenBev

I am British and have a British passport i also have dual-nationality and I hold a Irish passport this is due to the fact that my mother was born in the republic of Ireland that makes me automatically an Irish Citizen,
I obtained my Irish passport in October 2020 by supplying a certified copy of my mothers birth certificate, my parents wedding certificate, and my own birth certificate and it took only 4 weeks to complete I now have all the benefits of being a EU citizen including the right to live and work in the EU this is helpful to me as i have a residence in Spain that i can travel to Covid permitting as if i lived in Spain.

Hope this helps