Qty 1, $80 seems tolerable for a dev device. They should explicitly list 10 for $500 and 100 for $3000 or something though.
This is competing with $5-30K HSMs as well as $30-400 "hardware wallets" or second factor keys, as well as (free) embedded secure enclaves.
I would guess because of the FPGA. The advantage is it's (somewhat, arguably) more secure than a RISC-V ASIC from some random vendor.
Do not forget that they also need to recoup the $$$$$ spent getting it certified. For niche electronics this can be a big percentage of the price. Making something into an actual commercial product, especially globally, results in extra markup.
And they couldn't even put application ROM on there.