Will this stop a dedicated attacker? Probably not, although a fTPM with an up to date OS would require the attacker to find an exploit for this machine's early boot firmware (UEFI, etc) or burn a Windows zero-day, both of which are very costly.

It does however prevent your casual thief from watching a YT video "how to reset windows password using linux live cd" and then getting access to your sensitive data (browser's saved passwords, etc), so it's a major improvement.