iCloud Password Sharing Windows - Security Risk/Loophole

Isnt the iCloud password sharing with windows a huge security hole. I have a strong password on my iphone, I use face ID, my iphone geo locates me and locks me out if away from home if I try to change my password.

Move over to my PC, I have a simple 4 digit pin, if any, I install iCloud password sharing, I authorize via the 2 factor needed one time.

Then, afterwards the simple 4 digit pin will suffice, if i have one, and get this its the same as the pin for the computer. All the security on the iphone / apple end is eliminated by the windows security, which well, isn't much at all.

Therefore if I install iCloud for windows, i have basically created a backdoor to my passwords.