You can use the “program_ftdi” tool provided by Vivado to make the board detected, so that you can use it in Vivado. See here.
Vivado can then flash to RAM, but if you want to persist your design in flash, you still have to use the Alchitry Loader.
This is caused by the JTAG-to-flash bridge used by Vivado only support a few flash chips and being closed-source and non-documented (afaik) so it can’t be fixed so far…