Well, Pix is not free from those too... Besides being operated by the Central Bank, you still have to use your commercial bank account to send/receive money and, even though the Central Bank do require some minimum UX implementation standards, banks can still show messages offering lending services before you finish the transaction. So you also get banks already offer some kind of instant micro-loan even for small Pix transactions, just as you described.

At least most aren't as intrusive as Alipay, but they do exist.