One defense is to just have two banks, one for "real bills" and one for Zelle/Venmo "play money" bills.
Then at worst you're out the play money. Make sure it's set so the real money can only push into the play money account.
Then at worst you're out the play money. Make sure it's set so the real money can only push into the play money account.
I briefly looked into this at one point and as best as I could tell, Chase would only let you disable ACH on business accounts.
But ACH has much more defenses against someone pulling money than Zelle and friends do.