I read a funny the other day!
It goes like this:
“What do you think we used to keep snakes in twenty years ago? We’ve used fish tanks for sixty years! Fish tanks are great!”
Well, yeah, we also used to live in pleasantly-appointed caves and hunt with atlatls. Time marches on, brother.
The thing about fish tanks is that they’re designed for fish, which means they’re tall and narrow. (Most commonly kept pet snakes would prefer wide and shortish.) They’re made of glass, so at the size required for adult ball pythons or corn snakes, they’re brutally heavy. They’re difficult to get clean in those large sizes. When handling, you have to come in from the top rather than from the side. It’s transparent on all sides, leading to more stress, especially for animals in high-traffic areas. And, finally, while you can jury-rig them to get the right humidity and heat… why would you spend all that time fucking around when you could get a different type of cage that could have it all? CE, not BCE. Progress! Change! Get with the program! Lift your head out of your… fish tank.
You can use a fish tank if that’s all you have access to. You can even use it if that’s what you want to use - some people enjoy making their lives harder (see: Windows vs. Mac).
What I’d like to see an end to is the pissy, “I’ve been doing this for fifty years, every new suggestion is wrong, fishtanks as-is are just fine for snake keeping” because, goddamn it, they’re not - and there are better alternatives for new keepers now.