No financial sector does not mean no "markets". It means no providers of financial products.
However, some financial products emerge naturally between individual parties, such as credits and small-scale loans. I think the most noticeable loss would be the lack of mortgages (i.e. having to pay for a house up front). No simple means for online purchases would also be inconvenient (Bitcoin is still not a viable normal solution).
Didn't Ireland have a complete and total bank strike for a full year in the 1970's, with absolutely no negative side-effects?
As you've noted yourself, if you allow markets most of the rest kind of emerges. Futures and forwards are pretty natural, unless you somehow stop it, large scale loans are no less natural than small scale loans, products between individuals get outcompeted by products between individuals and larger entities.
Mortgages aren't great but having to pay for a house up front would move empower rentiers even further.
I just think you need to be specific, you're already down the path of realizing that some (but not all) of this is like laws of nature, saying that there's no value in a financial sector just seems ignorant.
Not sure of your age or nationality, but I'm guessing you didn't live through it. (I didn't either, for the record, but my parents did).
Ireland in the 70s was not a prosperous place, and trying to pay for things with second and third and fourth-hand uncashed cheques was a massive headache for everyone.
However, some financial products emerge naturally between individual parties, such as credits and small-scale loans. I think the most noticeable loss would be the lack of mortgages (i.e. having to pay for a house up front). No simple means for online purchases would also be inconvenient (Bitcoin is still not a viable normal solution).
Didn't Ireland have a complete and total bank strike for a full year in the 1970's, with absolutely no negative side-effects?