That essentially is what the big red main deck fire button does. Depressurise the aircraft. Probably of little efficacy against electrical fires or arcing etc. Anything involving lithium is of course seriously bad news. So they’re now attempting containment with special barriers / ULD’s etc.
Anything involving lithium ion / lithium metal on fire and you’re buying the farm unless you can get it on the ground / in to the ocean, ASAP. Literally minutes.
The Dash 8 can carry in excess of a 100 tonnes of the stuff. Some airlines, not all, ban the carriage of Li Metal batteries, a factor I believe in the UPS 6 tragedy. They are less restrictive when it comes to carrying lithium batteries in devices; tablets, the latest phones, etc etc. that we all have to have instantly.