I hear stuff equivalent to "Westerners moving to another country for a better opportunity" but overlook one detail: their citizenship is still from the USA / UK / AUS / NZ (so there's jury duty, right to vote, taxation, etc to take into account) in which those things still linger around even if you are not physically there, since it's heavily tied to what passport one carries.
I mean it like this, if one is held back by jury duty in USA / UK / AUS / NZ that makes it somewhat annoying to move abroad as it remains volatile whether you'll be summoned even in absentia or while preparing to move abroad, even if you explained and provided them proof that you are living abroad indefinitely: would that alone grant you a permanent excusal?
Some countries even have mandatory voting during elections (i.e. Australia), again that can be a set back for some. Civic duties such as being summoned by the court on being a potential juror or voting hold you behind when wanting to move abroad, as they can happen at any given moment. Renouncing citizenship of a "Anglo" nation rescinds all that.
Taxes are something EVERY nation has, there's no escape on that. However, for example the US is one of those countries that collects taxes based on citizenship: the solution for that is an American renouncing their passport ONLY if they are a naturalized citizen of the country they've moved to (which a US government official has to finalize & approve).
Depending on the country they have moved to: some countries have tough requirements for naturalization (as each nation has their own nationality laws) like Japan doesn't recognize dual citizenship (now requires 10 years permanent residency before elligibility) while some countries allow dual citizenship (i.e. Germany) with lenient requirements for elligibility.
Renouncing citizenship from your home country isn't a cake walk since it has multiple legal requirements and bureaucracy holds you back before being a naturalized citizen of the country you've moved abroad to. Like this, if you renounced your US / UK / AUS / NZ passport: that rescinds your ability to vote and no longer have to stress about jury duty.
Australians abroad can vote by mail or at their nearest consulate. No need to renounce your citizenship.
Yeah, unless you’ve been abroad for more than a few years without voting. Then your electoral enrolment gets cancelled. It can only be reinstated by returning and living in Australia for at least six (or is it 3) months.