I got some new Sandisk 32gb Ultra sdcards installed Pi OS on them etc - but when booting the Pi they gave the error in the title - all the same.
The sd's come with some software installed by the manufacturer which the Pi OS install program doesn't/can't clear properly.
So just format the SD's before you start using the official 'SD Association SD Card Formatter' software from here https://www.sdcard.org/downloads/formatter/
Once the disk is properly formatted, then go ahead and install your OS etc...
I now believe these were fake cards. They ran for a bit then failed.
I got cards from another source and it is clear (for instance) that the printing on the card is better quality (less bleed, less grainy etc), so I am returning the duds for a refund.
I would probably delete the question - but there is a good tip on the SD Association Card Formatter hiding faulty blocks which is useful to know if you are having card issues!