The “bin files” that are apparently shipping now with the device (unfortunately) were experimental and were only supported on the Pico (not the Pico2). They’re not something the community is planning to support going forward, because it wasn’t a very good option for several reasons. For more information on that, and what is replacing it, check this thread:
Also, here’s a great video showing and desribing the U2F Loader:
Currently, the UF2 Loader supports a number of firmware options like the MachiKania compiled BASIC, and a number of other firmware options. Community members are still trying out firmware on the new loader, and those updates can be found at the thread above. This has also resulted in some improvements in the loader too, as issues are found.
Unfortunately, PicoMite/Webmite requires some reworking since the way it handles flash is deprecated, and it doesn’t currently support the new loader. I’ve made an attempt to get it working, though I don’t really understand the details of flash access very well, or the changes that might be required. So far I haven’t been successful. I’m hoping others might be able to take a look at it and see what I’ve missed and maybe we can get it working. I’ve just merged the latest changes from the mainline PicoMite releases (which don’t, and never will, officially support PicoCalc) and I plan to get a release out soon once I’ve had a chance to test it a bit. (So probably later tonight or tomorrow.) This updated version won’t work on the UF2 Loader either, but it can be flashed directly like the previous versions. I have no plans to support the “bin” format for just the Pico, since no other projects seem to be moving forward with that and the U2F Loader is a better option.