An alternate perspective:
https://www.youtube.com/watch?v=DJD1gZNC1EMFWIW, I think it makes a lot of sense if you can't afford a higher end safe like Ft Knox w/ their add ons/armor upgrades. Browning safes are probably the cheapest I'd even consider insofar as trad'l safes on the mid to low end.
Also, take a look at Matt Risinger/the Build Show YouTube channel for lower-cost vault/secure rooms. They've had a few vids on that subject over the past couple years.
And don't forget you can build fire barriers outside of any safe/storage device too. Rockwool in walls, replacing drywall with fireboard, etc. Building a drywall/fireboard wall around safe (drywall to safe side of wall) with rockwool insulation and diamond mesh backing drywall or 3/4+" plywood to the outside, etc.
Basically, the safe itself is only one layer of protection. You want at least three layers and a security system in order to protect your stuff -- ideally one w/ automatic fire station alert for connected smoke alarms as well. Put one near/above your safe.
Three locks = home exterior, up-armored/reinforced gun closet, gun safe/storage device. Three to 4 walls = exterior, room in which closet is accessed, closet, add'l wall around safe for fire/attack protection. (Sides and back of safe are weakest/most vulnerable, with the door usually being the strongest component.) Etc.