It depends...
"How much do you love or treasure your equipment?"
"How much will it costs to replace them or send them for cleaning if fungus grows on the optical element?"
"How much are you willing to spend to protect your investments?"
My 2MP PnS digicam has been with me for 3 years and it has not been in a drybox and yet it's OK, no fungus yet....
But my 10 years old Rollei 35mm that my Dad passed me when I was young, has some slight fungus on the lens.
Used to own a $1k+ Prosumers camera, and that was what started me to invest in a drybox ($19.90 at Carrefour with hygrometer) and a bottle of silica gel $3-4
So, it depends on the value of the investment and how much are you willing to spend to protect it, like Life insurance, how much to insure your life for ($1m? $500k?) depends on how much are you willing to pay)
After I got a more expensive eqt, I upgraded to a dry cabinet.