Blik is explicitly not private in that sense, you have to trust your bank to use it. Not sure what they meant by that. However if your bank has a crappy online

Blik is explicitly not private in that sense, you have to trust your bank to use it. Not sure what they meant by that. However if your bank has a crappy online banking app and you live in Poland then you should probably change bank. The bank apps I've used as a foreigner living in Poland have all been essentially flawless (even using the English language versions).