The vast majority of users neither have a password on their computer, or if they have it it's a stupid one (like their name, their birthday, etc) or they have it written on a post-it that is attached on the monitor itself. Why do they need a TPM? Most of the time I setup a computer for a friend or family member they ask me to remove the password since they don't want to remember it.

Vast majority of users neither have that much important data to steal on their computer at all, just some family photos, some movies downloaded from the internet, there is the case of credentials saved in the browser, but the most important stuff (such as banking sites) nowadays requires a multiple factor authentication (such as password + OTP on your phone) to do any operation.