No
That's not true. Simple brute force attacks can kill passwords that use alphanumeric characters and they can do it quickly with passwords under 16 characters. Adding symbols and case increases the complexity exponentially. Current computer systems could take decades to brute force through passwords that contain letters (both cases), numbers and symbols at 12-16 characters. Adding characters increases the difficulty, again exponentially.
It's fairly simple math. If you only use alphanumeric (lets say only lower case) your password equals X^36 where X=password length. If you add both cases then it becomes X^62. Add symbols and it becomes X^94 on my keyboard.
So with 1 character you have 94 possible answers where one answer is your password. With 4 - 3.92318858 ?? 10^56. With 12 - 2.77355721 ?? 10^101. You get the idea. The complexity goes up really fast. Ultimately it comes down to how fast the computer performing the brute force attack can make posits. Most pros use graphics cards tethered together because they can affordable create systems that will run through a few million possibilities per second. But even with these machines some 16 character passwords can take over 100 years to break.
