Why does Bitcoin Core not support showing the prices in USD or other fiat currencies? One of the major annoyances I have with Bitcoin is that the only wallet/client I trust to some degree, Bitcoin Core, for some reason only shows sums in BTC.
Every time I want to make a transaction, I have to copy and paste sums from it to my special, separate calculator to get how much money it is. And when it's time to make the transaction, and it displays the fee amount, I see it only as BTC. I then have to manually type the sum in (since it doesn't let you copy the fee part) to see how much the fee is.
This minor detail really causes a lot of frustration. I truly don't get why they won't just add this.
And I don't agree with those who would say that this would require it to rely on some central entity, etc. The Bitcoin network, transferring tons of data around the clock, could very easily be made to keep track of a small blob containing the top currencies' exchange rates against Bitcoin. It would not violate anyone's privacy to have that extra data shuffled around, and it would not be part of the blockchain, but simply the &quot;RAM network&quot;, like all the other &quot;communication signals&quot;. It's a very minor piece of data, and infinitely useful. It could even have multiple different ones and let you choose which one you want to use.
Why do they not want to add this feature?
PS: I'm not going to switch to a different wallet/client. Please don't suggest that.
Why do they not want to add this feature?

There is no &quot;they&quot;. You can create issues or open pull requests to see feedback about a feature request from others.
Few reasons I would not want such feature in a bitcoin wallet:

Bitcoin Core wallet is an open source bitcoin wallet which is used by people from different countries with their fiat currencies. Lot of currencies and API for exchanges will be used to add such feature.

Bitcoin wallet doesn't need amounts mentioned in other currencies when it has its own currency which is BTC. I do not want to see amounts mentioned in EUR when I login to my bank account in India. Amounts mentioned in INR works better.