Yes, as it turns out fish does not recognize those kinds of redirects/command-substitutions.
Like .. you can .. but you need to add a special psub pipe to the end of each execution.
So something like the following would probably work;
bash <(curl -s https://cscs.pastes.sh/raw/aurvulntest20260611.sh | psub)
But it makes it unnecessarily longer with extra execution so I will stick to the single pipe to cover all bases while being succinct.
(It is in fact what I used to use as standard until replacing it with the first example you saw here.)
The OP has been edited to use the single pipe method for some hours now already. 