a 64 gb usb stick cannot be written or erased

I agree with both @Matti Haveri and @BDAqua.

Keep in mind the quality of USB sticks are extremely poor.....even name brands. I never use a USB stick for anything other than USB installers, or to quickly transfer an item to another system. I rarely use a USB stick for any important data unless I'm using a file system that is able to verify data integrity since I've seen so many USB sticks randomly flip multiple bits. Most USB sticks have no error correcting mechanisms unlike HDs & SSDs.

I had a USB stick where it appeared to work fine on one Mac, but could not be accessed on a second identical Mac (had a different version of macOS though). I could not even erase that USB stick on the second Mac. I had to first destroy the partition table on the USB stick before the second Mac could erase it, then the first Mac was unable to use the USB stick. I had never seen anything like that before. It was a name brand USB stick.

I had a USB stick where it appeared to work fine on one Mac, but could not be accessed on a second identical Mac (had a different version of macOS though). … I had never seen anything like that before. It was a name brand USB stick.

I had to toss a USB stick a couple months ago that was doing the same thing. And both Macs were running the same version of Sonoma. The only real difference was one is an M2 Pro mini, and the other a 2018 Intel mini. No matter which Mac I reformatted/erased it on, it couldn't be read on the opposite Mac.

But yes, you are absolutely correct that USB sticks are cheap because they are cheaply made (as the glacially slow write speeds attest to). And I use them the same way you do. Only as USB OS installers, or as a second (or third) backup of data. Never as a sole source of that data.

Thanks to HWTech...

For the "unable to write to the last block of the device" error, then I would suggest trying to erase the drive a second time immediately after you receive this error. I have encountered an intermittent issue where Disk Utility.

unable to write to the last block of the … - Apple Community

You can use Drive DX to possibly get a better view of Drive health…

https://binaryfruit.com/drivedx

Maybe the thumb drive is broken. Before getting a new one try to format it on another device.

BDAqua wrote:

You can use Drive DX to possibly get a better view of Drive health…

https://binaryfruit.com/drivedx

Unfortunately USB sticks typically do not have health monitoring.

Thanks.