That's a ridiculous point. Firefighters train to minize risks. They don't rush into a burning building through the hardest way in for FUN! They go through the most efficient and safest route possible to save lives!
You're mixing up two different things. Yes, they train to minimize risk
on the job...and their
hobbies are typically quite extreme. So for a lot of them, it's
fun to feel the adrenaline rush of extreme sports. And training to survive r
unning into a burning building doesn't preclude the adrenaline rush they get from
running into a burning building. Just because they're trained to minimize risk on the job doesn't mean it's not also
fun or that they don't
take risks for the fun of it. Both are simultaneously true: they minimize risks
on the job and
take risks because they're fun on and off the job.
Firefighters still value their own lives and they still have to evaluate risk all the time.
Not enough to avoid intentionally running into a building that's on fire.
Extreme sports enthusiasts still wear protective gear JUST IN CASE.
They're also legally required to. Take a look at YouTube and all the dumb crap people get up to without safety gear. Jackass is a famous example. Extreme sports have sponsors and insurance to worry about.
So yeah. If those tools are available IN-UNIVERSE and your character is aware of them? NOT using them would be a stupid decision on their part. Do your characters go into dark caves without a source of light because it's more fun?! No! They grab ask the Wizard to use his Light cantrip, or they grab a lantern, a torch or even a candle. If they have a Bag of Holding you better believe they'll stuff it full of rations, water and ammunition, even if you think micromanaging that stuff is more fun.
You seem to be confusing things a bit. Risking your life is inherent in extreme sports. They wear protective gear to minimize accidents and because they're legally required to. But death is always a possibility. Bungee jumping, base jumping, skydiving, etc. And yes, the extreme sports people wear protective gear...kinda like how adventurers wear armor...but they still willingly, regularly, and intentionally risk their lives for fun and profit. Now. Take away the insurance companies and sponsors. What would extreme sports look like? A lot closer to Jackass and the folks on YouTube. And D&D adventurers.
And we're not talking about real life. We're talking about elfgames. The characters who are D&D adventurers are adrenaline junkies who go into dark and dangerous places to murder whatever they find there, loot the place, and haul the treasure back to town to make themselves rich. They're not well-adjusted, clear-headed, right-thinking folks. They literally risk their lives for fun and profit. That's incompatible with "taking the safest route possible".
That low INT fighter isn't going to be wearing the best armor all the time. They're going to Leeroy Jenkins a lot of monsters. Sure, they'll die. But they're also too dumb to realize how much risk is involved. Again, it's about role-playing the character. I'm willing to bet your INT is higher than the 8 INT fighter. You are aware of the risks...that fighter probably isn't. So to role-play that INT 8 fighter you can't be overly worried about the risks. That's literally metagaming.