siri definitely has multiple timers. BUT you can only have two though and it only works on Apple Watch and HomePods.
I know, right?
Also a little known hack to set a timer you don’t have to say the whole thing just press the Siri button or say hey siri ‘n minutes’ and it will set a timer for n minutes.
"hey siri, set a 30 minute timer for the rice."
it works just fine for me, use it all the time.