I was looking into shared key encryption, found Shamir's Secret Sharing algorithm, found a GNU implementation called ssss.

Thank GNU

Many reasons to do that jump. I'll give two.

In some countries banks do collect automatically certain taxes that then go to the government. For example in the EU, in Belgium for example, if a stock I owned paid dividends and the bank is the custodian, the bank shall gladly take 30% off the dividends (+ add insane fees on top) and give that money to the government. As a sidenote it's wild that when you receive dividends in some countries you often end up with less than 50% of the actual dividends but I digress.

Still in Belgium: there's now an additional 10% tax on added value (since 2025), in addition to all the other taxes btw, that's always to be paid (say you sell shares of GOOG that went up... Even if you held for years: 10% are due in addition to all the other taxes on added values): and politicians are now wondering if those 10% shouldn't be seized immediately, with the banks collecting the 10% when you sell any equity (stocks/funds) and handing them over to the government. (so by the same mechanism that dividends are already immediately "taxed" by the bank).

"Banks to taxes" is a very real thing. Worldwide, but not in the US, there's the "Common Reporting Standard" (CRS): banks are basically little snitches that transmit all your accounts balances to the local IRSes. Which komrades shall hail has great progress but I digress again.

In addition to that banks have to comply with KYC/AML rules and are expected to do a certain amount of SAR (Suspicious Activity Report) to the government. Government which typically ain't much interested in crime: it's more interested in collecting money (like in the Al Capone case) on non-paid taxes (and the fines that go with it too). Ah, that's a third reason to do that jump: banks shall tell the government there's a suspicious activity from that person, governement then comes asking "where's that money coming from and where are the taxes you had to pay on that amount?".

I don't own any Monero but the link between "banks" and "taxes" is very real: I'm not saying it's good or bad. What I'm saying is that there's a very clear link between banks and taxes.

Now, and I'm still digressing, there are cases where the government/IRS ain't allowed to come see your accounts: some companies and individuals, in certain jurisdiction, have very strong protection against that (like actual jail time for bank employees that'd leak customers bank balances to journalists or the IRS). But, worldwide, it's not the norm.

And as I understand Monero, if someone has a balance in Monero on a self-custodian wallet, there's no bank that's going to report the balance to the IRS. Although now in the EU, for example, if you hold Monero on a centralized exchange (like Coinbase, the HN unicorn), then Coinbase shall send to your local IRS your balance of Monero each year to the government (it's a requirement of the MiCA EU legislation).

> Your own private bank which cannot interact with most financial institutions and merchants?

But you can gift $900 000 to the FSF which, itself, shall, I take it, have a way to transform these Monero into a currency that can interact with financial instutions and merchants right?

AIUI there are merchant accepting cryptocurrencies? Maybe not Monero but, still AIUI, you can use a decentralized exchange to convert Monero to another cryptocurrency the merchant accepts?

Additionally, banks are heavily government regulated entities, they are almost part of the executive branch. Aiding in the collection of taxes, neutering economic incentives for illegal activities, and implementing public economic policy are common and unquestioned responsibilities placed on banks through laws.

That's the whole point. Why would an privacy coin wanna interact with a corrupted banking sector? It's clearly not for you since you can't even see the actual point. You can use the banks, like everyone and let them profile (and sell your data), track and own your whole life.