I wouldn't say "better," just different. GNU Taler is centralized, so it's only as reliable as the issuer, whereas cryptocurrencies are as reliable as the distributed network. So Taler can't replace a fiat currency, it's just a toolkit to create your own fiat currency.

So it's great for privacy-minded folks in stable economies, but not great for international transactions or transactions where central authority isn't trusted. Essentially, cryptocurrencies are supposed to replace precious metals and whatnot for barter.

So I'm excited to see what privacy products people make with things like GNU Taler because it can be used today, but something like Monero is preferred if it can stabilize and start being accepted in more places.

I'm not saying government fiat currencies shouldn't exist, just that they aren't needed for regular transactions.

But the main problem with fiat currencies is that the issuing authority has a vested interest in tracking transactions. Cash isn't really a thing for digital transactions, and if the government realizes it can discourage use of cash, it will.

Fiat and cryptocurrencies can absolutely exist. Use fiat when interacting with the banking system (loans, savings, etc), and use cryptocurrencies like Monero for keeping transactions private (e.g. shopping). The government raising rates only really impacts borrowing, so companies and borrowers will use the local fiat currency and you'll get the desired effects.

what if the whole world replaced SWIFT with a private blockchain?

I'm honestly not familiar enough with international transactions to really weigh in on this. Maybe it's a good idea, IDK.

energy wasted on solving increases exponentially

Which is balanced by decreased value of additional coins, so less interested miners should drop out.

But the energy itself is kind of misleading, because miners will flock to lower cost energy, which should primarily be excess green energy. If we actually adopt this at scale, I expect energy companies to help in mining crypto with their excess energy generation, which should work well since that excess should be fairly consistent I'm a global scale.

That said, I'm extremely interested in seeing how proof of stake works out for Ethereum, since it just seems wasteful to mine coins for verifying transactions. But I think it's a lot less wasteful than opponents make it out to be.

you’re saying a buzz word without understanding the trade offs in designs… POW doesn’t have to imply higher energy cost for more transactions: shove more transactions in a block and POW cost is the same… that’s a trade off sure because then a block becomes a more valuable thing to 51%

POW is also only 1 of a lot of different consensus algorithms, all with their own trade-offs… POS benefits those with money for example (although you can still form mining pools - TBH i’d argue it’s exactly the same in this respect to POW in practice - good luck mining anything of value in POW without investing $ millions)

some blockchains aren’t built to be entirely trustless and uncoordinated, merely semi trusted and loosely coordinated (think a consortium of banks - they don’t trust each other entirely but a blockchain means no individual member working alone can cheat. in this case because it’s semi-organised they can use POS with a special token and delegate those “mining tokens” 1 per member of the consortium or something… you can even set this kind of chain up as an ethereum side chain!)