So, Matrix (federated) and XMPP (federated) would also have “metadata leaks”. I imagine there would be metadata exchanged between federated servers and in addition the E2EE of XMPP and Matrix is not so good/modern as Signal’s. When Signal-Whatsapp interoperability is mentioned, all people is worried about metadata leaks but it seems that concern dissapears when federation of Matrix or XMPP is mentioned.
Apart from that and one very personal opinion, I always connected Matrix to IRC, I mean, it is used more for the groups functionality than for the person-to-person functionality. And IRC was never considered an Instant Messaging alternative. But this is a very personal feel.
If you want to track all your wealth with one single tool (bank accounts, stocks, bonds, funds, properties…) I would recommend plain text accounting tools suchs as ledger-cli, hledger or beancount. I began with ledger-cli and move later to hledger.
You will learn a lot of double entry accounting and you will keep accounts with plain text files with version control.
It is a rabbit hole…