It’s not necessarily advised, but forcing strong passwords on your WooCommerce store can sometimes deter customers from processing their order. For the average person, the strength at which WooCommerce/Wordpress require their passwords to be is above and beyond anything the customer will remember. Personally, I use 1password to generate and store all of my passwords, so this is not an issue for me, but your customers may not be as tech-savvy.
Disabling strong passwords should be done at your own discretion, but until WordPress make the password strength parameters editable, I imagine many people will want to do it. You can add the following code to your theme’s functions.php file.